Awards > Awardee Interviews > Interview

Interview: Patricia A. Thiel

2014 Medard Welch Award Recipient
Interviewed by Paul Holloway, 2014

HOLLOWAY:  Let me welcome you.  My name is Paul Holloway.  Today is Thursday, November 13, 2014.  We’re at the 61st Annual International Symposium of the AVS in Baltimore, and I’m joined in interviewing Dr. Pat Thiel from Iowa State University by Dan Dougherty from North Carolina State University and Dick Brundle, an AVS member from California.  So Pat, let me congratulate you on being the 2014 Medard Welch Award winner.  Your citation reads, “For seminal contributions to the understanding of quasicrystal surfaces and thin-film nucleation and growth.”  So congratulations.
THIEL: Thanks, Paul.  Thanks.
HOLLOWAY:  Let me begin by asking you to give us your birth date and birth place.
THIEL: Sure.  I was born February 20, 1953 in Adrian, Minnesota in the middle of a blizzard.
THIEL:  [Laughs]  I was born and raised on a farm, and when my mother was pregnant with me, my father heard the weather forecast.  In those days, it was quite common for us and other farmers to get snowed in for days at a time, and the last thing my father wanted to do was to deliver his own child!  [Laughs] 
HOLLOWAY:  I don't blame him!
THIEL:  So he heard the weather report.  He took my mom to stay at a hotel in town.  [Laughs]  Then he went back to the farm to take care of the animals, and I was born in the middle of that blizzard.  They even had trouble getting my mother from the hotel to the hospital, which was about three blocks away.  So it was a good thing he did what he did.
HOLLOWAY: Wow.  You’re a unique individual.  [Laughs]  Let’s see.  Let me continue by asking you to give us something about your educational background.
THIEL:  Sure.  So I went to elementary school at a Catholic school in a little town called Lismore, Minnesota, which was about three miles from our farm.  I went there through grade eight, and then I went to a public school in Adrian, the town where I was born, for the four years of high school.  We didn’t have junior high in those days.  I went to college at Macalester College in Saint Paul, Minnesota, and I’m ever grateful to the Reader’s Digest because they are what got me off the farm basically.  [Laughs]  My father made a deal with me.  He said, “I will send you to a state university, but if you want to go anywhere else, you have to find the money yourself.”  So under his terms, I would have gone to a four-year state college that wasn’t too far away from home, but thank goodness I got a National Merit Scholarship from the Reader’s Digest.
HOLLOWAY:  All right!
THIEL:  And that is what enabled me to go to Macalester, which was considerably farther away from home, and it was in a big urban center, meaning, the Twin Cities area.  It really opened up new vistas for me.  That was great.  I went to college knowing I wanted to major in science, but I didn’t know what kind of science.  My freshman year I took freshman chemistry from a very gifted teacher, a guy named Emil Slowinski, and Emil was  a commanding presence in front of the classroom.  He also interacted with the students regularly, calling on them and  jousting with them and engaging us.  He was so inspirational that I decided to go into chemistry as a result of that class.
HOLLOWAY:  Wonderful.
THIEL:  When I was a senior in college, I started working as an intern at a company called Control Data Corporation.  In those days, Control Data Corporation made big mainframe computers, and it dabbled in a lot of other things as well.  But they had a couple of little analytical chemistry laboratories, and I worked in one of those.  Then after I graduated from college, I took a year off and worked at Control Data Corporation.  They were such a small operation that I ran the laboratory for them.  [Laughs]  But that was a lot of fun because I got some experience with SEM and with atomic emission spectroscopy. And various other laboratory analysis techniques.  It was great fun, actually, to have problems walk in from different parts of the company and try to analyze them. 

I remember one problem.  There was a production line, and I might have the details a little bit fuzzy, but this is the general story.  As part of their process, they were sandblasting something with a water solution, water and sand mixed together, and they had a contamination problem after this process.  They suspected that there might be some contaminant in the solution that they were using.  So I  did a little organic separation and extracted the organic component and analyzed it with infrared and found out that it was their pump oil.  [Laughter]  They just needed to fix the damn pump!  Which they then happily did and the problem went away.  But solving those kinds of problems was really interesting and gratifying. 

Of course I couldn’t solve all of the problems.  A lot of the problems  consisted of trying to identify some green crud that was growing on a chip that had failed in life testing.  So they would get a bunch of chips in from another company and they would subject them to relatively high temperature and high humidity.  Some of them would fail, and if the failure rate was too high, they wanted to ship them back.  Of course they had to prove to the original company that this batch had failed, so they needed my data in order to prove that.  The more information they had, the better, so if they could identify what the corrosion product was, then that was a better case.
BUNDLE:  Environmental stress tests is what they call them, right?
THIEL:  Okay.  Okay.
BUNDLE:  I did a little bit of that at IBM.  I never could understand, though, how they knew it had any connection to reality.  [Laughter] 
THIEL: True.  True.
BUNDLE:  It was just “We’ll treat this as badly as possible and if it fails, we’ll say that, well, it isn’t going to work in our product.”
HOLLOWAY:  That’s right.  Yeah.
THIEL:   They were  a small operation. One of the more interesting things that they did, speaking of IBM, was to send me little tiny flakes of paint and of polymer and ask me to identify them as well as I could.  I couldn’t do much with them.  Finally I said, “Why can’t you give me more sample?” and they said, “Well, we’re renting a unit from IBM and we have to return it to them intact.  So we can only take little tiny pieces.”  [Laughter] 
BUNDLE:  So they won’t notice.  [Laughs]
THIEL:  Yes, yes.  “But we want to copy it if we can.”  [Laughter] 
BUNDLE:  That is very interesting.
THIEL:  IBM was  the competitor on a pedestal.
HOLLOWAY:  So you worked for CDC for a while.  Then you went on to graduate school then?
THIEL: I did, because as much as I enjoyed it there, I could see that with a bachelor’s degree I wasn’t going to go anywhere.
HOLLOWAY:   Absolutely.
THIEL:  People with graduate degrees were being promoted like that [snaps fingers].  So I didn’t really want to be stuck at that level for all of my life, so I decided to go back to graduate school.  That was good.  It gave me some motivation for graduate school that I wouldn’t have had if I had gone straight out of college.
BUNDLE:  Can I go back to Macalester, right?
THIEL:  Right, right.
BUNDLE:  I’m not that familiar with the American system, but that’s a pretty well-known liberal arts college.
THIEL:  It is.  It is.
BUNDLE:  In fact, my friend Dave Fowler went there, and I’ve met several other people.
THIEL:  David Fowler was in class with me!  Yes!
BUNDLE:  Okay.  I never knew that!
THIEL:  We took physics together.  We took an electronics class together.  Yes.
BUNDLE:  Yes.  So being a liberal arts school, I don't  associate that with science.  Did they have a lot of people who went there without  a direction but had their minds really open and had really good teachers and then…?  I mean you said you got into it because of the teacher basically.  Did you have any intention in going that direction before you met him?
THIEL:  I wanted to go into science.  That was for sure.
BUNDLE:  You already knew that, yeah.
THIEL:  And I was at Macalester because I knew that going there enhanced my chances of getting this National Merit Scholarship because they had a high percentage of National Merit Scholars funded by Reader’s Digest.  They have a special relationship with Reader’s Digest with the DeWitt Wallace family.  So I think that they like Carleton and St. Olaf’s and other fine small colleges.
HOLLOWAY:  Yeah.  Exactly.
THIEL:  They attract a lot of students who probably do want to go into science but have a  nebulous idea of exactly where they want to go.  Yes, I think that’s-- 
HOLLOWAY:  If you go back through the interviews, it’s remarkable how many of the people have started off in small liberal arts schools, especially in the Midwest area.
THIEL:  Yes.  Nowadays I think they’re being hurt by the emphasis on engineering because none of them offers engineering as an undergraduate major.
BUNDLE:  I’m sorry I deflected you.
THIEL:  No, that’s okay.
HOLLOWAY:  So you decided you needed to get a graduate degree.  What year was this?
THIEL:  This was, I think, 1976 or so.  Well, 1975 would be when I was applying for graduate school.
HOLLOWAY:  And where did you go?

THIEL:  I went to Caltech.  I interviewed at a number of places.  I wanted to do analytical chemistry, and that was exactly the period in time when in chemistry, analytical chemistry was unfashionable.  So academically it was being subsumed into physical chemistry.  So for instance, I applied to Stanford and was rejected because they said, “Poo-poo.  We don’t do analytical chemistry.”  [Laughs]  So it came down to MIT or Purdue or Caltech for me, and Caltech  treated me so wonderfully on the interview trip that I decided to go there.  My hosts on my interview trip were Jack Beauchamp and Frances Houle.  Frances of course is nowadays one of the co-directors of JCAP, right?  But she worked with you for many years at IBM.
BUNDLE:  Yes, in IBM research.  Yeah.
THIEL:  Yes,  Anyway, they treated me very well.  And then I always gained some pleasure out of the fact that I went out and got an NSF Predoctoral Fellowship, and after that, Stanford called me up and said, “Oh by the way, you know you can come here after all.  We really do do analytical chemistry.  We just don’t call it analytical chemistry.” 
HOLLOWAY:  [Laughter]  There is pleasure in that.
THIEL:  Yes, there is pleasure.  But by then it was too late.  And I’m happy I went to Caltech.  Caltech is a great place.
HOLLOWAY:  Who did you work with at Caltech?
THIEL:  Worked with Henry Weinberg because I was interested in surface science.  At that point in time, it was the really new, breaking, up and coming field, so that attracted me. So I went to work for Henry Weinberg.
HOLLOWAY:  What did you work on?  What was your subject of your dissertation?
THIEL:  High-resolution electron energy loss spectroscopy and temperature-programmed desorption, mainly of water on ruthenium(001).
HOLLOWAY:  Is that right?
THIEL:  Yes. And you know, that was in the day when water was  an adventurous molecule to work with.  [Laughs]
BUNDLE:  That’s got three atoms.  [Laughter]
HOLLOWAY:  Yeah!  And more than anybody else was working with!  [Laughs]
THIEL:  And I remember as a graduate student, what tremors went through the community when Brett Sexton reported some investigation of formic acid and people went, “Wow!” Because everything was carbon monoxide and oxygen and maybe nitric oxide.
HOLLOWAY:  Yeah, if you want to be adventurous.  Yeah.
THIEL:  Yes.  So I think  my claim to fame in my thesis work was elucidating the importance of hydrogen bonding in the two-dimensional surface layer.  Proposed a model for it which built on the model that Ted Madey and John Yates had proposed based on ESDIAD, which of course later proved to be wrong.  Largely wrong, at least.  But still, you know…
HOLLOWAY:  That’s the danger of being first in the field because everybody’s trying to prove you wrong then.
THIEL:  True.  Science is an iterative process, and I don't so much mind being wrong. To me, to be really embarrassed, there would have to be some ethical breach, right?  But everybody makes mistakes.  If you don’t make mistakes, that means you’re not doing anything.  It’s those mistakes and the mistakes getting corrected by which we move forward.
HOLLOWAY:  Exactly.  Yeah.  So after you finished your PhD at Caltech, where did you go then?
THIEL:  Before we leave Caltech, can I   say how much I enjoyed some of the group members there?  One of them in particular was Ellen Williams.  We were in Henry’s group at the same time.  In fact, we collaborated on one project at one point.  And so we’ve been friends ever since, and I  have the greatest respect for her.
HOLLOWAY:  Any other group members you remember?
THIEL:  Oh sure, sure.  Lots of them.  Glenn Thomas, Bill Bowser, Howard Evans, Michel Van Hove, and Sheng-Wei Wang were in the group at the time.
HOLLOWAY:  Quite a list of names.
THIEL:  Lynn Forester, Jenna Zinck.  And I think not many of those have gone on to academic positions.  Dale Ibbotson, Steve Wittrig.  But you know, they’ve all gone onto very successful careers.
DOUGHERTY:  I’ll just comment.  Ellen was my thesis advisor.
THIEL:  Oh wow!
DOUGHERTY:  Yeah.  So I’ve actually heard lots of stories about the Weinberg group in that era.  Ellen would always use stories from that time to make us feel better when we had made some terrible mistake.  [Laughter]  She would tell us how John Yates had nicked a knife edge with his screwdriver and not to worry about what you had done because that was the worst thing ever.  [Laughter] 
THIEL: Oh, and thank you for bringing up John Yates.  He became a visiting professor while I was a graduate student.  He kind of adopted me, and we worked together really closely in the laboratory.  He taught me almost everything I knew on a  day-to-day basis, and I was so lucky to have that happen.  He  changed my life for the better.
BUNDLE:  He kind of adopted Henry as well, fortunately.  [Laughter] 
THIEL: Okay.  So after graduate school, what did I do?  I put myself on the job market.  IBM didn’t hire me.  [Laughs]  But Sandia/Livermore wanted me, and I said to Sandia/Livermore, “You know, I really want to do a post-doc.”  I had an offer of a post-doc from both Ertl and Menzel, both in Munich at the time, and so I told Sandia/Livermore, “I really want to do a post-doc.”  They said, “Oh, that’s okay.  We’ll hold the job for you for a year,” and I thought, “Man, that’s a deal!”
HOLLOWAY:  Can’t beat that.
THIEL:  Yes.  So I went off and did my post-doc with Ertl in Munich, and then I came back to Sandia in Livermore.  While I was with Ertl in Munich, I originally was supposed to work on this project that was rather hot at the time, which was nitric oxide scattering from platinum(111) in the rotational state distribution of the scattered molecule, and somehow that  didn’t click with me all that well.
I happened to be talking to other people in the group about what they were doing, and  latched onto a project to study CO oxidation on platinum.  The central part of the project was to try to figure out why this reaction would oscillate under some conditions.  I remember the day that Jurgen Rüstig discovered oscillations in the reaction kinetics on platinum, and that was so exciting, you know, because you could do this in UHV.  So then I started working closely with Jürgen Behm, and we investigated the adsorption of CO on platinum.  It became clear after a while that the reconstructions were very important, at least under these conditions, in facilitating the oscillations.  So Jürgen and I, and Peter Norton who was visiting the group at the time, did a lot of work to clarify the interaction of oxygen and CO on a fundamental level.  What was really interesting was the idea that CO—and we got this all from LEED; this was before STM—the idea that CO could lift the reconstruction and create a 1×1 on the platinum(100) surface in a localized area.  We could figure out the local coverage of CO for that to occur.  You know, it had all the trademarks of a first-order transition and nucleation and growth type process.  That in turn actually clarified some of the infrared data that David King had obtained a few years before. It was an exciting time.

I remember working many nights till the wee hours in the morning and getting in the next day by 10 a.m. to start the experiments again, and it was a lot of fun.  And then meeting up with Peter in the Mensa to have coffee and talk about what was going on in the lab, and he would always be full of ideas.  He was a wealth of information.
BUNDLE:  It’s interesting because all these people that you mention also had AVS as a good part of the history of their careers. 
HOLLOWAY:  Exactly.  Yeah.
BUNDLE:  Well, I haven’t seen Peter Norton around for a while.
THIEL: He retired about four or five years ago.
BUNDLE:  I guess that’s why then.
THIEL:  I think he moved out to Vancouver to be closer to his daughter.
HOLLOWAY:  I’m curious.  I want to take a sidetrack and not lose the main track.  But what did your mother and father think about you going to Germany?
THIEL:  Oh…  [Laughs]  Well, they never quite knew what to make of the whole deal, you know.  They grew up in immigrant farm families.  When they were educated, an eighth grade education was something to be really proud of, and they both were very proud that they had finished the eighth grade.  And they were very proud of me when I finished high school because that was one step beyond and they could  understand one step beyond.  College?  Well, they didn’t know what to make of college.  But then graduate school?
HOLLOWAY:  Yeah, this is crazy.  Why are you quitting your good job to…?
THIEL:  Yes, exactly.  And they couldn’t understand why anybody would pay me to go to school, you know?  How could I possibly be supporting myself when I was just going to school?  So they were proud of me, but they never understood what the game was all about.
HOLLOWAY:  I understand that completely.  I didn’t want to distract.  Let’s go back to the main theme.  You were in Munich now and you were having a good time.
THIEL:  Yes, I was having a good time!  Then I moved back to the United States.  I had to take this job at Sandia, and I worked at Sandia Livermore for about a year and a half.  That was the time period when we got to know each other, I think.
THIEL:  And I got to know quite a few other people at IBM through Jürgen Behm, who was also in the Bay Area at the time.
BUNDLE:  Yeah, Jürgen was working with me, and I know you met my wife.  You’re one of the few science people that she remembers, actually.  [Laughter] 
THIEL:  And Dan Auerbach and Paul Bagus.  It was a great cohort of people.  So I worked at Sandia-Livermore, but when I had interviewed there, Jimmy Carter was president.  Then I went to Germany for a year and came back, and by then Ronald Reagan was president.  When Jimmy Carter was president, there was a huge emphasis on solar energy and renewables.  Sound familiar?  And in the blink of an eye, when Ronald Reagan became president all of that went away and it became weapons.  So I came back to a different Sandia than I had interviewed at.  The interesting thing to me, though, was how facile they were at converting their technical expertise between the solar energy and weapons.  They had never lost sight of the common base.
BUNDLE:  Did they actually convert it or is it like many things in IBM research where people actually said they were converting to do with something and they carried on pretty much doing the same as they did before?  [Laughing]  But with just a slightly different long-range plan.
HOLLOWAY:  That’s very typical.
BUNDLE:  So whether it did or they really dropped programs and start completely new ones.
THIEL: I wasn’t intimately involved with the organization when it made this transition, so I can’t answer your question.  I just saw the effect. So I came back to a different Sandia than I had left and rather quickly found that I was  not comfortable with the weapons research.  In spite of any  political bent that you may or may not have, or that I may or may not have,  the thought of a nuclear weapon being used—and going to work every day with that as an objective—made me wake up at night from nightmares of a nuclear holocaust. I couldn’t live with that.  I understand science and technology is a continuum, and you never escape from the possibility that something you do can be used in a bad way.  You have no control over how your science and technology may be used.  It’s not black and white; it’s gray.  But I  realized that I would be more comfortable over in another part of the gray spectrum rather than that part.  So I decided to look for an academic job.  But in between, I quit Sandia, or I was fired, depending on how you want to look at it.  So I had a few months in my professional life to fill. I can’t quite remember the sequence of events.  I was interviewing for academic jobs, and I got an offer from Iowa State to start in August of 1983.  I think I had a few months to kill professionally before that position started, so I  cast about.  I don't remember how it happened, but I found out that the group of Paul Richards at Berkeley had an experiment and they were looking for some help from a surface scientist.  So I moved up to Oakland because I couldn’t find any place in Berkeley that was politically compatible to live in.  [Laughter] 

First of all, I   wanted a place for a few months, so I was  looking for a room in a house or some communal living arrangement.  Most places didn’t want anything to do with me, when they found out that I had the aura of a weapons laboratory.  I remember one place said, “You have to be a strict vegetarian to live here,” and I said, “Well, I’m not a vegetarian, but I promise I won’t bring any meat products into the house.”  They said, “No, no, no.  That’s not good enough.  If you’re not a vegetarian, you would probably wear leather, like leather shoes or leather belts,” and I said, “Yes, I would.”  So that was the end of that.  [Laughter] 
HOLLOWAY:  It was a different place.
THIEL:  It was a different place for sure.  [Laughter]
BUNDLE:  I wonder what your mother and father would have made of that!  [Laughter]
THIEL: Oakland was the only place that would accept me, so I lived in Oakland for those few months and worked with Shirley Chiang and Roger Tobin in the Paul Richards laboratory.  They were doing this incredible thing: Building an infrared bolometer to look at infrared emission from a surface and thereby examine very low frequently modes, especially the natural linewidth of the metal carbon stretch of CO on nickel (100).  It was a technical tour de force, and these two people were just graduate students! They were working with very little guidance from Paul Richards.  It wasn’t anything that he had done before.  In the fashion of Berkeley or Caltech or MIT, he had  assigned them this incredibly hard project and said, “Go do it.”  [Laughter]  And they did it!  But they got to the point of trying to prepare clean nickel (100) and they couldn’t get a LEED pattern.  So somehow Paul Richards found money for me as a temporary visiting post-doc or whatever, and I went there and I cleaned the nickel sample for them.  We got a LEED pattern and we got an infrared spectrum, and that was great fun.
BUNDLE:  So you weren't hired at IBM, but you are responsible for Shirley being hired at IBM.  [Laughter]  We hired her on the basis of that work!
THIEL:  Oh no, Shirley is responsible for Shirley being hired at IBM.  [Laughter]  She is such, such a world-class experimentalist. World-class physicist, I should say. So then I went to Iowa State in 1983 and have been there ever since. I had a low sticking coefficient for a period in my life, and then I stuck.  I moved out of the mobile precursor state and-- 
HOLLOWAY:  You fell into the deep trap.  [Laughs]
THIEL  Yes, I fell into a deep trap at Iowa State.
BUNDLE:  And that area is…  I interviewed there once before I ever went to IBM, and the main reason I didn’t want to go there is because of where it was and being so isolated.  But you’re a farm person.  Did that have any influence on it?  It was kind of a familiar environment that you were happy to move back in because of your original upbringing?
THIEL:  Mixed feelings.  In the time away from the Midwest, I developed a true love of mountains and mountain scenery, so it was hard to go back to the flatlands of the Midwest.  On the other hand, the Midwestern culture is something I’m very comfortable with and I appreciate it— more so, I have to say, than the culture of California. As I was driving out of northern California on my way to Iowa, I had the radio on, and there was a news article about a kind of a cult called Breatharianism.  There was a guy who for some exorbitant amount of money would teach you how to live off of air alone because, you know, your digestive tract really was  a remnant from a lower evolutionary stage.
BUNDLE:  What radio stations do you listen to would be my response.  [Laughter]
THIEL:  And you know, I  thought, “This guy would never make a penny in the Midwest because nobody would buy it!”  But in northern California, he was doing quite well.  So I’m more comfortable with the culture of the Midwest, I have to say.
DOUGHERTY:  When you took the position at Iowa State, was Ames a factor at all?
THIEL:  Ames Laboratory?
DOUGHERTY:  The Ames Lab, yeah.

THIEL:  Yes.  It was both directly and indirectly.  It helped fund my appointment, and it certainly had contributed to the reputation of the University.  Both of those were factors.  Plus I think it was the only place that offered me a job, so that was a factor, too.  [Laughter] 
HOLLOWAY:  That can be a minor factor.
THIEL:  Yes.  [Laughs]
HOLLOWAY:  I think that what Dan was referring to perhaps was there’s some connotation of weapons.
DOUGHERTY:  And that’s what I was—the connection between Sandia and Ames and their different missions maybe?  I don't know.
THIEL:  Well, Ames Laboratory doesn't have a weapons mission.  It did, of course, in the Manhattan Project when all the national laboratories were birthed.  But it hasn’t done any classified work for a long, long time.
HOLLOWAY:  So you went to Ames.  I must tell you that when I was at Sandia in Albuquerque, there was a group leader there that was from the University of Iowa.
HOLLOWAY:  And he had a sign on his wall saying, “Remember Iowa is a four-letter word.”  [Laughter]  So you’re Iowa State, so I guess you’re all right there.
THIEL:  Yes, yes.  [Laughter] 
HOLLOWAY:  So what did you do when you arrived at Iowa State?  Was the lab established for you or did you have to create your own lab?
THIEL:  Oh, the lab wasn’t established.  I was given a few small rooms in one of the Ames Laboratory buildings, but there was an older professor, for whom I have increasing sympathy as the years go by, who was  on his way out.  But he wanted to retain a little research effort, and I  had to push him out of his space in order to gain some space of my own. I was fortunate in getting a UHV system from a gentleman named Bob Hansen.  He was a giant in the field of surface and colloid science in the earlier days, in the pre-UHV days.  He had bought one of the Varian LEED/Auger LEED chambers and he gave it to me, and that allowed me to get off to a pretty quick start.  So I built that up.  I developed video LEED capability, high resolution EELS capability, TPD.
HOLLOWAY:  Did you build all of these or you got money and bought the equipment?
THIEL: All of the chambers were either put together or heavily modified in a piecemeal fashion.  For example, with the TPD, of course you buy the mass spec, but you build the shrouds and the little dosers and all that.
HOLLOWAY:  Right.  Were you alone in the surface science area at Iowa State or were there other people already in a surface science area?
THIEL:  No, I was alone, except for Bob Hansen but as I mentioned previously, he wasn’t really a UHV scientist. And also I was the first tenure-track woman on the faculty for a long time.  Actually, Iowa State has a good tradition.  In the early days it had women faculty, but then it went through a period in the ’50s and ’60s when there were no research faculty women.  So I was the first one to come on board in a long time.  I remember what a relief it was when there finally was another woman hired after me—her name was Theresa Cotton—because up until then, I had the sense that when I gave a talk or when I directed my students in research, people looked at me and said, “Hmm.  So that’s how a woman does it.”  [Laughter]  And of course, I’m just one person and there are lots of different styles.  So it was a relief to have another woman there.  But aside from that, I must say I was always very comfortable at Iowa State and was made to feel quite comfortable.
HOLLOWAY:  I must admit that I was surprised when Ellen said last night that you were the first woman recipient of the Welch Award.
DOUGHERTY:  You’re kidding!
BUNDLE:  No.  I was, too.  It’s just something I’ve never thought about.
HOLLOWAY:  So congratulations!  You’ve broken the mold here, so to speak.  [Laughter] 
THIEL:  Yes.  And hopefully there will be more.
HOLLOWAY:  Hopefully there will be more.  I’m sure there will be more.
BUNDLE:  Yes.  I called my wife last night and told her you got…you’re here and got this award and everything and that you were the first woman.  She made a very derogatory remark about the AVS.  [Laughter]
HOLLOWAY:  Well, what was surprising to me most about that was if you look at the history of the AVS, Dorothy Hoffman was an early woman president, and there have been a whole host of them through the years.  So I’m just surprised that it took this long to get into the awards ceremony.
THIEL:  I was also the first woman to win the Adamson Award of the ACS, which is, or has been at least, their top award in colloid and surface science.
HOLLOWAY:  Well, congratulations on that as well!
THIEL:  Thanks.
BUNDLE:  When was that?
THIEL:  That was 2010.
HOLLOWAY:  So let’s talk about your research program at Iowa State.  You continued along the veins that you had developed in Munich for research?
THIEL:  I did, and the video LEED was one of the most interesting things that we did in those early years.  I continued a little bit with my research interests in water, and that brought me into a collaboration with Ted Madey where we joined forces to write the Surface Science Report that has been cited so many times.  But up until that point, Ted and I hadn’t really known each other very well, and we certainly hadn’t worked together on anything. Boy, he really committed to that project, to writing that review article.  He said, “Okay, Pat.  I’m going to come out to Iowa State for this week in February and we’ll work on the review article.  Then I’ll come back again in July and we’ll work on it for another three days,” and he did!  I mean he was really dedicated, and it was a big deal.
DOUGHERTY:  Where was he at this time?  Rutgers or NBS?
HOLLOWAY:  NBS, I believe.
THIEL:  NBS, yes..  So that was how that article came to be published.  Our editor was Charlie Duke, another really famous surface scientist.  I never heard what happened to Charlie Duke. 
BUNDLE:  He did pass away.
THIEL:  Did he?
BUNDLE:  Heart attack, I think, wasn’t it?
HOLLOWAY:  I’m not aware of that.  He went from being a director at Xerox-Webster to a position in Virginia, and then went back to Webster for a while, then retired in Virginia.  The last I knew he was retired in Virginia.
THIEL:  Oh, okay.
BUNDLE:  When was that?  How long ago?
HOLLOWAY:  Five years.
THIEL:  And he was such a great editor, you know.  We wrote this very long article, and he dissected it word by word, both stylistically and scientifically, and  made it into a much better article. I actually hired a summer intern   to keep track of the references.  Of course that was before the days of endnotes.  [Laughs]  Yes.  So that was how that got published.  We also discovered the isotope effect in the thermal desorption of water from ruthenium(001), which I think is what ultimately planted the seeds for Dietrich Menzel to do the LEED-IV analysis of D20 on ruthenium, which is one of the pieces that ultimately led to the correct picture for this nearly planar, partially dissociated structure.
HOLLOWAY:  Ted Madey was a wonderful person.
THIEL:  Oh, yes.  Whenever I think of a model of professional scientific behavior combined with a human element, I think of Ted, you know?
HOLLOWAY:  Yeah.  He was a true gentleman.
THIEL:  Yes.
HOLLOWAY:  So did you have other people come to Iowa State and work with you?  Or you worked with other people and went to them?
THIEL:  Mmm.  You know, I should have looked over my list of publications before I came here.  My memory is a little bit fuzzy on that.
HOLLOWAY:  Well, you can add some of those names in editing if you want to.
THIEL:  That would be nice.  That would be good. 
HOLLOWAY:  Okay.  So how did your program develop then, once you went past the LEED and video LEED?  How did it develop into quasicrystals, for example?
THIEL:  Oh, okay.  Well, one big development was STM.  Another big development for me was meeting my husband, Jim Evans.  We struck up a collaboration.  He’s a theorist, and we’ve had a very fruitful theory/experiment collaboration almost the whole time I’ve been at Iowa State. I started to work in the area of nucleation and growth.  Well, some of the video LEED work had naturally led in that direction as well.  In the late ’80s, early ’90s, with STM we started to see really interesting and unanticipated things in terms of nucleation and growth and behavior of islands.  I think we were the first group to see that a big two-dimensional island of metal atoms on a surface could actually migrate intact over distances of on the order of 100 angstroms— significant distances.  And we were again, I think, the first group to see that these islands could bump into each other and merge, and we studied the kinetics of that process.  I think that data is still being used today as  a benchmark for theoretical simulations because you have to get a lot of the energetics right in order to describe that merger.
DOUGHERTY:  This is silver on silver(100)?
THIEL:  Yes, it is. More recently we became interested in the effect of adsorbates on these processes, nucleation and growth, but even more so on coarsening processes.  It really started when two of my students, Tony Layson and  Jian-Ming Wen, were doing various kinds of experiments with these silver islands.  They had an accident.  You know how it goes.  A little leak sprang in the middle of an experiment, and what they saw was that immediately all of these islands  disappeared.
HOLLOWAY:  Just disappeared.
THIEL:  Just disappeared.  [Laughs]  And we said, “Wow!  What’s going on with that?”  So we decided to start to track it down and found out that oxygen was probably the culprit, and very low levels of adsorbates can have this effect.  Oxygen was hard to work with.  It was hard to control the coverage of oxygen, so we moved to sulfur, which is easier to calibrate, easier to control, and that’s led to some of the work that I talked about on Wednesday, which is really interesting to me.  You know, at very low coverages, we’re seeing these complexes form between the metal and the adsorbate.  I didn’t talk about all of them, but we’ve seen some on silver (111) that are very ornate.  It’s amazing that these things can assemble as they do.  So that’s one of the things I’m most interested in these days. 

Quasicrystals.  Quasicrystals.  In the late ’80s and 1990s, I had a project to look at the surface chemistry of fluorocarbons (somewhat related to lubricants and magnetic disks) and that  petered out.  We had done some work that I thought was nice, but I was looking for a new project.  My colleague in Ames in the Physics Department, Alan Goldman, had been working in quasicrystals almost since they were discovered, and he said, “Hey, why don’t you work on surfaces of quasicrystals?  There’s almost nothing that’s been done there.”  So that was how I started working on surfaces of quasicrystals, and it’s been really great fun because we got into this field at a point where there had been a few experiments done.  I’m not saying we were the first to ever work on a surface of a quasicrystal.  But those few experiments were really not accepted by the quasicrystal community.  The quasicrystal community was  poo-pooing them.  Nobody had done a concentrated, sustained investigation.  The ones that had gone before were   little one-off efforts…  You know, try and get your PRL and then go on and do something else.  So we did the sustained investigation that convinced the community ultimately that the surfaces were bulk terminated.  I remember going to an international conference in Strasbourg on quasicrystals and showing our evidence that surfaces were bulk terminated, and a gentleman named Christian Janot stood up and said, “This is impossible.  Your data must be wrong.”  [Laughs]
BUNDLE:  French, no doubt. 
HOLLOWAY:  Yeah!  That sounds like Charlie Duke and Max Lagally!  [Laughter] 
THIEL:  And Peter Feibelman.
HOLLOWAY:  Yeah, Peter Feibelman.  [Laughter]
BUNDLE:  What was your response to that?
THIEL:  I don't remember. 
BUNDLE:  Were you just kind of shocked and didn’t want to give him an answer in kind?
THIEL:  I don't remember.
BUNDLE:  You don’t remember.
DOUGHERTY:  So when I think about this kind of thing, my first comment is getting samples of quasicrystals isn’t completely trivial.
THIEL:  No, it’s not at all!
DOUGHERTY:  So how did you get samples in the early days, maybe, when they were still kind of unusual, or more unusual than they are now?
THIEL:  When we started, there was one kind of quasicrystal that people could grow as macroscopic single-grain equivalent to single crystal samples, and that was aluminum-palladium-manganese.  So we started with aluminum-palladium-manganese.  I have colleagues in Ames who are excellent scientists and also excellent growers of single crystals.  Paul Canfield is probably at the top of the pyramid in that respect.  And eventually, Paul became very interested in quasicrystals, but at the time I started he wasn’t there yet. Luckily, another colleague named Tom Lograsso could grow beautiful samples of aluminum-palladium-manganese. 

 But then we managed to get Paul interested in quasicrystals, and everything he touches  turns to gold.  And lo and behold, he applied this method that he calls flux growth to developing beautiful macroscopic samples of quasicrystals.  It opened up the field.  At the same meeting in Strasbourg that I told you about, I showed the little dodecahedron on a penny picture that I showed on Wednesday, and the audience literally gasped.  [Laughter]  And then there was a murmur, and a friend of mine in the audience later told me that the murmur was people turning to each other and saying, “Look at the scale.  Look at the penny,” because they had seen images like this before, but only in electron microscope images.
BUNDLE:  That is amazing.
THIEL:  That opened up the possibility to grow macroscopic high quality samples of different kinds of quasicrystals.  So that ultimately led to the ability to grow the decagonal phases, the aluminum-nickel-cobalt, and that led to the friction experiments.
HOLLOWAY:  So you were lucky to be at Ames in that respect.
THIEL:  Oh absolutely!
HOLLOWAY:  And they were lucky to have you go to in that direction.
THIEL:  Oh, vice versa.  Yes, yes.  Absolutely.
BUNDLE:  I think that happens a lot in environments like that where there’s a nucleus of people.  Some people have one kind of expertise, in this case crystal growing; others have others, and as long as there’s communication, there’s good stuff you can do.
HOLLOWAY:  Right.  You have to have communication.
BUNDLE:  I would probably never have got anywhere but for being at Bell Labs, there were all the people…  Two sets of people, one who grew xenon, made rare gas compounds.  So they were pretty unusual, right?  And then the theoretical people on the other side who did calculations.  And I’m sitting there and I can take the photoelectron spectra of these.  So the three together were meaningful, whereas one on its own is not nearly so interesting.  So I think it’s really good to be in an environment like that where there are a lot of other people.  Some scientists do the opposite and they kind of isolate themselves and just work on their own.
THIEL:  You know, some people need to do that.  There needs to be a diversity of modes of operation.  I think there’s a quote by Einstein in which he says, “If you want me to produce garbage, force me to collaborate.”  [Laughter] 
BUNDLE:  I didn’t know that!  Okay, I withdraw what I just said.  You can strike it when you edit.
THIEL:  No, no, no. The collaborative atmosphere is great, too.  I’m just saying that there needs to be room for a diversity of styles. 
BUNDLE:  He also said he wasn’t sure whether there was a limit to the universe, but he knew there was no limit to man’s stupidity.  [Laughter]
HOLLOWAY:  Now that we’ve established the bounds for this conversation.  [Laughter]  So tell us a little bit about the quasicrystal surface investigations.  What has resulted from that?
BUNDLE:  At this point, I have to go.  I have an appointment at ten, so I have to leave.  I listened to the talk, so I know all about it, and I’m sorry.
THIEL:  That’s okay.
BUNDLE:  It’s great seeing you here.
THIEL:  Yes.  Thank you.
BUNDLE:  And congratulations on both this and being the first woman to win the award.
THIEL:  Thanks, thanks.  And say hello to Jenny for me, please.
BUNDLE:  I will.  I will.
THIEL:  Okay.  So in terms of the quasicrystal research, probably the biggest things we did were first of all to gather a lot of evidence that the surfaces were bulk terminated.  But the nail in the coffin was the LEED-IV analysis, and for that I  carefully cultivated a collaboration with Michel Van Hove.  He in turn had this superb post-doc named Martin Gierer, and together they--  We took the LEED-IV data and they did the multiple scattering, the dynamical scattering calculation.  They had to develop a technique to treat a system that was not periodic, right?  So they had to really push the boundaries, and what they did was, for the in-plane atomic structure, they developed a kind of a pair correlation function approach to the atomic positions.  And of course they kept the interplanar spacing.  They took a bulk structure model of quasicrystals and because no two planes are identical, that was also  a challenge.  What they did was to say, “Okay, if this plane is the termination, what IV factor would we get?  Then if the next plane is the termination…” and they  kept stripping off planes and figuring out what the IV factors were.  They noticed that the IV factor was oscillating, so when they would hit a certain kind of a plane, a certain kind of a termination, the IV factor would be lower than it was otherwise. This clued us in to the idea that there were a family of planes that were possible terminations and not just a single termination.  When they calculated the IV factor for this mixture of terminations, they got really quite good agreement.  That result has been substantiated.  It was later substantiated by an x-ray photoelectron diffraction study that included multiple scattering, and other types of studies as well.  So the idea that quasicrystals are bulk terminated is pretty firmly established, also for other kinds of quasicrystals like aluminum-nickel-cobalt.  That was a big deal.
HOLLOWAY:  Now you used LEED for this, and when I think of LEED, I haven’t heard you mention STM before.  How heavily did you get into STM to correlate with the LEED analysis?
THIEL: Eventually very heavily.  But the LEED in the beginning was a standalone investigation.  At first we didn’t use STM to investigate the quasicrystal surfaces, and looking back, I guess I wish I had pushed harder to use STM early on.
HOLLOWAY:  Yeah, because I think of the silicon reconstructed surface, for example, where there were several different models that could explain the LEED data, and until you had the STM data combined with it, you didn’t know which was the correct model.  So is that same situation true for quasicrystal surfaces?
THIEL:  The STM has confirmed what the LEED-IV found—that we can explain the surface structure in terms of bulk termination.
THIEL: I showed an image of the fine structure on Wednesday, and we can really explain all of those features like the cut clusters in terms of bulk termination.
DOUGHERTY:  Can you describe how you got into the STM field sort of from starting out with what I guess I call traditional surface science tools, LEED atrials?
THIEL:  Had to.  Everybody had to.  Couldn’t get a paper published unless you had STM data.
DOUGHERTY:  When was this and how did you go about doing it?  Did you build a bunch of STMs?  Did you get funding to buy one or could you buy one?
THIEL:  This was in the late 1980s, and we had our first STM…  Well, we built it like all of our systems in those days.  We cannibalized other systems and cobbled it together from other parts, and we bought the STM and the electronics, of course, but everything else was home-built or cannibalized.  [Laughs]  Nowadays it’s much more common to buy complete systems.  National Science Foundation, by the way, paid for that original STM and they paid for a subsequent STM, and the Department of Energy paid for a subsequent STM as well.  Only two of those STMs are still working, though.  Anyway, you had to  do STM.  Just like today you have to do DFT, right?
HOLLOWAY:  So do you still collaborate with your husband now in terms of DFT and other theoretical approaches?
THIEL:  Absolutely.  He has incorporated DFT into his arsenal of tools, but he still is more of a statistical thermodynamics person, as he always was, or statistical mechanics person.
HOLLOWAY:  So you met him once you were at Iowa State?
THIEL:  Yes, I did. We started dating after I’d been there for a couple of years.  So we have never had to both look for jobs simultaneously, which has been a real gift, and it turned out to be a great place to raise our kids.  We’ve been happy there.
HOLLOWAY:  How many children do you have in your family?
THIEL:  We have two daughters.  The oldest one just graduated from MIT in June.  She is a materials engineer.  She’s now working for Exxon Mobil in Baton Rouge.  Our youngest is a mechanical engineer major at Cornell, and she is intensely involved in an underwater autonomous vehicle team project that they have there.  It’s an underwater robot that thinks for itself, and the things that it can do are quite amazing.

HOLLOWAY:  That’s remarkable.  It sounds like you’re proud of them.
THIEL:  Not like I’m proud of them.  No, not at all.  Just ask me about them; I’ll tell you everything.  [Laughs] 
HOLLOWAY:  I’ve read your write-up for the awards that you put together, and you have a whole host of honors.  Would you tell us a little bit about some of the honors that you have received?
THIEL:  Yes.  It’s always amazing to me because it seems that there are so many other people that are more deserving.  I had a National Science Foundation Presidential Young Investigator Award, which was the predecessor of the career awards in the early days.
HOLLOWAY:  Did that help you get off the ground?
THIEL: Absolutely.  And it gave me a degree of freedom that was wonderful.  I had a Sloan Foundation Fellowship and a Dreyfus Foundation Teacher Scholarship.  Those were both wonderful gifts as well.  I have an honorary degree from a university, Université de Lorraine in Nancy, France.  I have won the Adler Lectureship Award of the APS and the Adamson Award of the ACS.  Those were both in 2010.  I’ve won teaching awards from the University and from the department.  I won a service award from the college.
HOLLOWAY:  Quite a list.  Tell me about the honorary degree from Nancy.
THIEL: Oh, that was instigated by my friend Jean-Marie Dubois in Nancy, one of the giants in the field of quasicrystals.  He was the person who really broke open the whole area of interest in surface properties of quasicrystals.  He was the one who measured the low coefficients of friction and derived the low values for the surface energy and pointed out their potential applications in coatings and in composites.  So he was the one who nominated me and  arranged for that.  I have been privileged to be a visitor in his laboratory for several summers in the early 2000s, and I got to know him quite well then.
HOLLOWAY:  Tell me how many laboratories you have visited.  Can you give me any feeling for that?  I get the impression it’s just a very large number.
THIEL:  You mean visited for a collaboration?
HOLLOWAY:  For some collaboration, some period of time.
THIEL:  Yes, it is a large number, and I probably-- 
HOLLOWAY:  Is it 10?  Is it 100?  Is it 1,000?
THIEL:  It’s probably somewhere between 10 and 15. So maybe not such a large number.
HOLLOWAY:  Well, that’s a large number in my opinion because that’s an extensive commitment on your part, a significant commitment on your part.  I notice that you were an Invitation Fellow of the Japan Society for the Promotion of Science.
THIEL:  Yes!
HOLLOWAY:  Can you tell me about that?
THIEL:  Oh yes.  I was privileged to spend two weeks visiting the group of An-Pang Tsai at NIMS.  Tsai is also one of the giants in the field of quasicrystals.  He has discovered many of the quasicrystalline phases that we know about.  He’s very creative in his hunt for new quasicrystalline phases. I was able to visit him and I learned a lot about his approach to quasicrystal discovery, and then subsequently I also visited him in Japan at Tohoku University in Sendai, the city that was so affected by the big earthquake and the tsunami.
HOLLOWAY:  Right.  That’s quite an adventure.
THIEL:  Yes, it was.  It was great.  I loved being in Japan.
HOLLOWAY:  You’ve participated in AVS for a number of years, but I see that you have received the Adler Lectureship from American Physical Society and the Adamson Award from ACS that you mentioned earlier.  Tell me your perspective on interaction with professional societies.  I’m not trying to get you to rank AVS versus the others, but what I’m interested in is why you worked with a spectrum of societies and what you gained from that.
THIEL:  Well, as you know very well, surface science is a highly interdisciplinary topic.
HOLLOWAY:  Absolutely.
THIEL:  We, myself included, tend not to look so much at whether a meeting or a group of people consists of chemists or physicists or material scientists so much as we look at what they’re working on and is it of interest to us.  So I think that is a very good reflection on the nature of the field itself, this cross-disciplinary, interdisciplinary nature, and surface science has been interdisciplinary long before it was fashionable to be so.
HOLLOWAY:  Right.  Yeah, I think that’s one of the unique aspects of AVS, in fact, the degree of interdisciplinarity in the Society.
THIEL:  Yes.  What I enjoy so much about the AVS is that it is, in my mind, a very good size. When you go to a meeting, you can see everybody you want to see.  You’re not lost in a huge sea of faces.  And it’s small enough that you can jump around between the sessions to see the talks that you’re really interested in.  Of course at the bigger conferences like ACS, sessions are distributed over different buildings and there’s no way you can jump around, and that’s not to be derogatory.  I think the larger societies certainly play a role and have their place, and especially in terms of being…not spokespersons, but spokes-entities for the scientific community.  They have a lot more clout than a smaller society like AVS.  But AVS represents a more cohesive community, I think, than the other societies do.
HOLLOWAY:  What advice would you give to a young person thinking about getting into the field of surface science, for example?
THIEL:  Well, the ones that are getting into surface science are doing exactly what needs to be done. I would say, be as broad as possible in your interests and don’t limit yourself to work in ultra-high vacuum because it’s increasingly difficult to fund ultra-high vacuum instrumentation and equipment for the purposes of a single investigator.  It seems increasingly that the only way to fund that kind of equipment is through a big center proposal, and then it has to really be a multipurpose piece of equipment.  So I think surface science is changing, and I think it’s changing for the better. 
HOLLOWAY:  We certainly are working with more complex molecules on surfaces than we were before.
THIEL:  Yes!  Yes.  The sky is the limit, eh?
DOUGHERTY:  I mean can you comment on this more?  I’ve heard even going back to when I was a PhD student, you know, “Surface science is too mature,” you know, MRSEC reviews and things where that’s sort of the end result.
THIEL:  Really?  Hmm.
DOUGHERTY:  You know, “You need to expand your horizons.”  When you said you see it’s changing for the better, what specifically?  Moving out of UHV?  What are you thinking?
THIEL:  Moving out of UHV, or at least using UHV as a complementary technique, not a standalone, a sole technique.  I think that’s a good thing.  One of the things that worries me, though, is we know so much in surface science, and I think that there’s a real danger that a lot of it is being lost.  I don't want to be too negative, but so much of what we know can be transferred to other disciplines—nanoscience, material science—and that transfer isn’t always taking place very efficiently.  So to some extent I’m a little afraid that people will spend time reinventing the wheel.  But on the other hand, maybe that’s just the way it has to go.  What do you think, Paul?
HOLLOWAY:  I agree that it’s changing.  I think it’s moving out of the UHV; I agree with that aspect as well.  But I think the molecules are more complicated.  I think we are losing some of our past history in all of these because a lot of them will do a Google search and they’ll come up with the last ten years of effort, but not go back to beyond that.  The days of people going, students going to the library and looking up papers is done.
THIEL:  Yes.  It’s not only that, though.  That  puts the blame on the student or the researcher.  But even a researcher who wants to dig and find the information simply doesn't have the time or the resources.  The amount of information that’s available is overwhelming. So one of the things I do worry about is information transfer.  It seems to me that really the most effective means of information transfer is and always has been documentation like textbooks and journal articles supplemented and complemented by human interaction, right?  For example, you told us that you remember the stories about John Yates and the knife edge—stories that you heard when you were a graduate student with Ellen Williams.
DOUGHERTY:  The stories, yeah.
THIEL:  Clearly it was Ellen’s interaction with you that left you with some lasting memories and ideas of how to think about problems.  So I worry a little bit about the frailty of that element in information transmission, that human connection.  I know when I’m in a classroom teaching, my students are going to study.  They’re going to study the paperwork; they’re going to study the textbook.  But I also think I’m a good teacher, and their understanding of the material is enhanced greatly by our human interaction in the classroom.
HOLLOWAY:  Absolutely.
THIEL:  So I worry about the frailty of that connection and  …
HOLLOWAY:  How easily it’s lost.
THIEL:  Yes.  Exactly.
HOLLOWAY:  I think it’s particularly important that we maintain the interactions not only in the student-teacher relationship, but within the professional societies, the peer-to-peer relationships as well.  That’s why I think it is so important to have professional societies and attend those meetings.  I like to tell my students, “You’re smart when you get your PhD, but you’re going to be learning the rest of your life.  How do you learn the rest of your life?  You have to learn how to learn in a professional society forum in order to continue that education over your lifetime,” and that’s why I strongly encourage the students to come to these meetings, for example, and get that experience.
THIEL:  And ask questions and talk with the speakers, yes.
HOLLOWAY:  Yes.  So we agree on that.  I think that covers a large part of what I wanted to cover today, Pat.  Do you have anything you’d like to add?
THIEL:  Oh, when we were talking about the quasicrystals, I wanted to add that I think that one of the nicest things we did was studies of friction on the quasicrystal surfaces.  We collaborated…  I believe in collaborating a lot because to be honest, I think that’s the most efficient way to do things.  I might have a colleague who knows everything about carbon nanotubes, and by working with that colleague, it’s easier to bootstrap.  So in the area of friction, we worked with Andy Gellman for a time and got some very valuable information.  Then we worked with Miquel Salmeron and Frank Ogletree at Lawrence Berkeley National Laboratory, and I think that was one of our major contributions to the field of quasicrystals, too.
HOLLOWAY:  Good.  Anything you want to add, Dan?
DOUGHERTY:  No.  Thanks!
HOLLOWAY:  Well, let me congratulate you again on the Welch Award.  Well deserved.  Very impressive history.  You’ve done a lot of excellent work.
THIEL:  Thanks, Paul.