Articles by: Kenneth Hanson

Photo Friday (#picpickoftheweek)

My graduate student, Sean Hill, became the Hanson Research Group twitter account manager last week. We first talked about what is and isn’t acceptable to post on the internet. Then Sean explained to me the nuances of hash tags and how I’ve underutilized them.  He also suggested something brilliant: a photo of the week.

One of the things I like most about doing research in molecular photophysics is the beautiful color chemistry. Now, every Friday, Sean will tweet (#picpickoftheweek) our best photo taken during the prior week. Our first image (below) is very fun and depicts a photon upconversion solution.

Upconversion

This image shows green laser pointer light (532 nm) causing blue (~430 nm) emission from the solution.  What makes this image really interesting, from a photophysics standpoint, is that we’re  observing the conversion of lower energy green photons into higher energy blue photons.

The reverse—higher energy blue light turning into lower energy green light—is easy. Many molecules absorb a single high energy photon and then emit a single lower energy photon with some energy lost in the process due to vibrational relaxation.  The more difficult green-to-blue light change depicted above is only possible if we combine the energy from two green photons to produce one higher energy blue photon.  This process is known as photon upconversion.

While it can be observed in inorganic nanoparticles, the solution above is a mixture of two types of molecules that undergo excitation, energy transfer, triplet-triplet annihilation and then emission.  Our research group is interested in studying these upconversion systems because they could potentially provide a mechanism to harness low energy light and increase the theoretical maximum solar cell efficiency from 33% to >40%. If you’re interested in learning more about photon upconversion through triplet-triplet annihilation, here is a good review article.

Follow us, @HansonFSU, on twitter for more molecular color chemistry.

By January 18, 2014 4 comments fun

Recapping Mike Shatruk’s AMA

Mike Shatruk, chair of Florida State University’s chemistry graduate recruiting & admissions committee, hosted an AMA (ask me anything) on reddit.com/r/chemistry last week. Over a span of three days, he answered redditor’s questions about applying to graduate programs, factors in admission decisions, faculty advisor selection, and more. A recap of the AMA is shared below (Quick note: Some of the content has been edited for clarity and grammar/spelling).

Application Process

Can you give us a short summary of how FSU does its admissions process?

-Chemjobber

Mike: We ask students to submit their:

  • GRE scores
  • Unofficial undergraduate transcripts
  • CV
  • a personal statement
  • three recommendation letters
  • a ranked list of three programs of interest (choose from analytical, biochemistry, inorganic, materials, organic, physical)
  • a ranked list of three professors the student might be interested to work with

After the application deadline, the admissions committee divides students by research interests and 1-2 committee members review applications in each respective area and make admission decisions. Each student is admitted individually. It’s a lot of work, but we believe we should dedicate time to screening our applicants as well as we can.

Can you please briefly explain currently the best approach for overseas students to search for suitable positions. From memory, so please correct me if I am wrong… 1) pass GRE, 2) Identify desired Universities, and 3) submit application by Jan/Feb in order to start in August.

-ItsAllChemistry

Mike: Yes, you’ve got the right sequence in mind.

  • Pass GRE and make sure the scores satisfy the program-stipulated minima (we ask for at least 150 on verbal and 155 on quantitative parts of the test)
  • Get a copy of transcript from your undergraduate institution * Look through the list of US universities with PhD programs.
  • Write a 1-2 page personal statement as to why you would like to apply to a particular program, what prior research experience you’ve had if any, who of the professors you are thinking to work with (doesn’t have to be just one person), what your career goals are, etc.
  • Compose a brief CV to go along with your application
  • Get three people to agree to write your letters of recommendation
  • Submit the application package as described by the program. For FSU graduate program, you can check this link for international students.

When does your program typically send out acceptance letters/emails/notices? 

-Jeol

Mike: Usually we sent our acceptance letter from January 15 to February 15. We typically give you 1-2 months to report whether you’d like to attend our visitation weekend. IMPORTANTLY, following the Resolution by Council of Graduate Schools, no school can push you to accept their offer prior to April 15.

 

Application Materials

Grad schools generally ask for thing like GPA, letters of recommendation, research experience, and test scores. How much weight is applied to each one and/or which is most important?

-RBWoodward

Mike: To answer your first question, it depends on the particular school, but in principle, all the components of your application are important. I would say that most PhD program value some research experience. GRE scores are usually viewed as reflection of your intellectual ability, and your GPA indicates how well organized you were in your undergraduate courses and if you’ll be able to stay focused in your PhD pursuit. Finally, the letters of recommendation often help to improve the value of your application if your referees have something really good to say about you. At FSU we consider each case individually and carefully. We also know that sometimes a low GPA is not a real reflection of student’s ability, in which case we review the trends in your grades to see whether you’ve been improving toward the end of your undergraduate education.

How does a minor in a related field factor into your decision (I’m MSE but have a chemistry minor)?

-danny31292

Mike: The major/minor relationship really depends on the school you’re applying to. For example, we have a very active and broad materials chemistry program, so having an MSE student with a minor in chemistry will be viewed positively.

What little unknown things can we do to help us get into our first choice grad school? 

-RBWoodward

Mike: Make sure that your scores and grades are above the minimum requirements that the school stipulates. It would be better if they not just above the bar, i.e. if the requirement is 3.2 GPA, then it will be better to have 3.4 and higher. Also, work carefully on your personal statement and make sure your application is complete and submitted on time.

Ken: One trick for getting into the school of your choice is to try and do summer research at the university before applying (sophomore or junior year). You can do this through either an REU program or simply contact a professor directly to see if they are taking summer research students. If you work hard and show that you are competent it is the best summer long interview you could possibly give. If the rest of your application package meets the minimum requirements, the advisor would be hard pressed to say no to a competent student joining the program.

I’m a UK undergraduate, currently applying to Master’s programmes in Europe. I was wondering if the Master’s is really worth it if I apply for a PhD in the US. Would I effectively do another Master’s as part of that, or could I sort of skip ahead?

-Kalivh

Mike: We actually like international students with Master’s degrees, because they come somewhat more prepared for PhD program. Yes, you’ll be taking some coursework again, but you will be likely to go through it faster. You also will have a faster start-up period in the lab, if you’ve done research as part of your M.S. degree. The research experience in the UK is just as valid as that in the US. Basically, we just would like to see that you’ve been in the lab and experienced some research environment, so it’s easier for you to get started. We also need to see that you are interested in research, because that’s what the PhD degree is all about.

Does having a B.A. vs a B.S. make any difference in getting accepted?            

-altqq

Mike: B.S. is preferable, but it also depends on what courses you have on your transcript. If you took a lot of science courses and have good grades in them, then you have good chances.

 [I was doing well and then my grades plummeted.] What advice can you give me if I am sure I want to pursue a graduate degree?

-Thrownawaymyacademic

Mike: You’re in a tough spot. One of your options might be to seek a summer research opportunity in some school to which you’d like to apply. You could just apply to some lab as a volunteer giving the argument you’ve just presented above. If you’re lucky, you’ll get your chance. And if you prove yourself to be much better than what you grades tell, then maybe the professor you have worked for will vouch for you as an exceptional case.

 

Admission Decision

Is there anything you frequently see in an application that make you dismiss an otherwise likely candidate (something they write in the statement of purpose, ect)?

-Joje0904

Mike: Regarding your question about obvious flaws in the application, those would be (1) missing the deadline. It shows that you’re not very well organized and serious about the process; (2) something negative your referees have to say about you – and I mean negative, not just critical (some criticism never hurts); (3) deteriorating grades toward the end of undergraduate school – they indicate that you are currently academically weaker than in the beginning of your studies, that you don’t do very well in senior-level courses, and that you’re likely to fail in graduate-level courses for those two reasons.

How much importance do you place on an applicant’s undergraduate school?

-velvetjaguar

Undergraduate schools do matter, but if a student has good grades and test scores, as well as research experience, he or she has just as much chance to make it as a student from a higher-ranked school with lower grades. Again, each case is individual, but we tend not to discriminate applicants based on their undergraduate schools.

How screwed am I if I don’t have any research experience?

-Ben

Mike: It’s important, but not necessary. If your grades and GRE score and recommendation letters are strong, then you have a chance. We also offer an optional bridge summer research opportunity for students who have been admitted to our program, which in your case might be a good option. Again, without research experience all your other markers have to be pretty strong.

Could an excellent Chem GRE score (ie 95+ percentile) offset a mediocre GPA even if the Chem GRE was not required?

-Sophia7X

Mike: Perhaps, but I cannot answer that because we do not require Chem GRE. You’ll be better off asking the specific school directly.

How much do admission committees value the experience gained from professional employment?

-head-splitter

Mike: Your industry experience is likely to be viewed positively, as it suggests you might be more mature in your attitudes and seeking the graduate degree to better your professional opportunities.

 

Salary/Benefits

How much does FSU pay their students? Do they receive benefits?

-EagleFalconn

Mike: Our graduate stipend in 2014-15 will be $21,500 per year. Out of the fees you pay, about 50% comes back to you as a reimbursement later. The health insurance subsidy is $1,300.

PhDstudentslave: Looking at the FSU program they only pay their students $20,000, however they then charge their students about $1,000 in fees each semester, (Fall, Spring, and Summer) leaving them a mere $17,000 a year. I believe the only perk the students get is subsidized health insurance option (~$800 a semester).

Spookyjeff:  I’m a chemistry graduate student at FSU. I’d like to note that in the area you can live comfortably on the stipend without much effort

Ken: Cost of living is something to consider rather than just the dollar amount. Here is a simple cost of living calculator. For example $20,000 in Tallahassee is equivalent to $21,500 in Chapel Hill or $26,000 in LA or $32,500 in San Francisco.

How soon is funding discussed in your program? Is it detailed along with acceptance?

-Jeol

Mike: Funding situation depends on the specific school. At FSU Chemistry and Biochemistry, we guarantee funding to all admitted PhD students at least for the first 5 years, which we believe is sufficient for graduation.

Choosing a Research Group/Advisor

Is it rude for me to bother an adviser’s other students to get a feel for how they treat their students?

-Joel

Ken: you should definitely talk to the adviser’s current grad students before joining a group. The adviser can easily put on a facade when you meet and greet but hopefully their students will give you real insight into the group/research/adviser. If the students don’t want to talk to you that is probably a red flag about the group dynamic and social environment. Remember that you will spend the next 4-7 years with these coworkers. You want and will need people that are willing to go out of their way to help you. Asking questions before you join is a good way to test the water.

hstlives: My former advisor would encourage prospective students to meet with his current students. When you speak to a professor about joining his/her group, bring up the topic of meeting their students and see if they help you out with the initial meeting.

Mike: You most definitely want to talk to students from the groups you’re interested in. A rare advisor will tell his or her students not to indulge you into learning about their experiences in graduate school. It is very important that you join a group whose research is truly interesting to you and where you can see yourself fitting well not only intellectually but also socially.

What’s the best way to go about contacting a research advisor about joining their group?

-velvetjaguar

Mike: If you are interested in research done by a particular faculty member, I suggest e-mailing them directly. They usually will reply promptly to your request.

Why is it so important to find a good advisor?

-SafeInTheArdennes

Mike: It’s probably the most important choice you’ll make in graduate school. You’ll have to work with that person and his or her research group for 5 years, on average, and to be successful, to build a strong resume, you need to be comfortable in your work place, get good and thoughtful advices, expand your knowledge and skills, and know that if you do all that your advisor will support you in all future endeavors with strong recommendation letters.

What advice do you have for applicants as far as selecting an advisor?

-THEchemgirl

Mike: You certainly need to look at possible advisors before applying, because you don’t want to apply to a school, get in, and then find that nobody does any research that interests you. When you attend our visitation weekends, which serve as preview of the program for admitted students, you’ll have a chance to speak to 5-6 faculty members. Once you start in the program, you’ll be able to listen to brief presentations in which faculty describe their research projects. You will also be able to talk to many faculty and students before making your final choice. Most schools give you a few months from the start of the program to pick an advisor.

 

Other

Does FSU have a program for graduate students for teaching chemistry or chemical management?

-Thorisgodpoo

Mike: We attempt to educate our graduate students toward diverse career pathways, including research, industrial (management), or teaching careers. Two most important things you learn in graduate school are how to do independent research and how to teach others about chemistry. You’ll have a chance to TA in the lab or at recitation session. Usually students who are looking into teaching careers prefer to do recitation sessions, because those really let them experience how to explain concepts to students in classroom setting. Some of our senior graduate students who would like to apply for teaching jobs are even given a chance to lecture for undergraduates, and we are currently working on making such experience into a permanent program. That being said, having done a strong PhD will let you keep your options open to other career choices.

How likely are credits to transfer from undergrad to graduate school? I’m taking a few extra graduate level classes to supplement some of my learning and wondering if I should just audit it.

-lammnub

Mike:It depends what school you are attending (i.e. the school rankings and rigorousness of the coursework). We usually allow transfer of up to two courses, but typically that policy applies to students who have completed master’s coursework. Nevertheless, we will consider your request for the transfer of graduate courses if you’ve been admitted to our program.

How bad is it to do your undergraduate and PhD at the same university with the same professor?

-manar2710

Mike: In the United States it’s not very typical, but it does happen. In European and Asian countries, that’s a norm. Anyway, what you’ll be judge by in the first place is your productivity and the quality of your work (the number and impact of publications). But having the BS and PhD from the same place might be viewed just a tiny bit negatively when you apply for a faculty position. Nevertheless, a strong PhD and a productive postdoc experience (at a different place, I hope), will cancel out that very quickly.

I hesitate to use the terms “grade inflation/deflation”, but how does the choice of undergraduate university affect your perception of GPA?

-Paradigmist

Mike: We are aware of those issues, and we usually factor them into consideration, although it’s not easy when you get applicants from hundreds of different schools. So, our judgment is based on our previous experience with applicants from particular institutions.

 

By December 9, 2013 0 comments Uncategorized

Aspiring Graduate Students: You have questions, Mike Shatruk has answers!

Are you thinking about applying to a chemistry graduate program? Do you have a few questions first?

  • What is the application process?
  • What items do I need to gather in order to apply?
  • What is the most important part of my application package?
  • How soon will I hear back after applying?
  • What should I consider before accepting admission?
  • How do I choose an advisor?

Mike Shatruk is an associate professor of chemistry at Florida State University and chair of the Chemistry and Biochemistry Department’s graduate recruiting & admissions committee. He will host an AMA (ask me anything) on reddit.com/r/chemistry/ on Monday, December 2nd beginning at 10:00 am (EST).

If you have a question but won’t be able to post them on December 2nd, share it in the comments section below and I will make sure he gets it. I’ll also compile all of the questions and answers afterwards and post them on this blog.

Update: Here is the link to the AMA.

By December 1, 2013 5 comments Uncategorized

Rethinking the Jablonski Diagram

I am teaching a course titled “Spectroscopic Characterization of Molecules, Materials and Photovoltaics.” The first few lectures were on molecular photophysics and included a thorough introduction of the Jablonski Diagram (For anyone interested, my lecture ppt slides are available here).

The Jablonski diagram, first introduced by Aleksander Jabłoński in 1933, is a graphical depiction of the electronic states of a molecule and the transitions between those states. The y axis of the graph is energy, which increases from the bottom (ground state or S0) to the top (singlet and triplet excited states or Sn and Tn). The transitions between the states—like excitation, internal conversion, fluorescence, intersystem crossing, etc—are depicted as arrows. Because of its simplicity, the Jablonski Diagram is a starting point for many discussions about the events that occur following electronic excitation of a molecule.

Plain Jablonski

I am new to teaching and spent a lot of time thinking about what homework I should give my students to both facilitate learning and gauge their understanding of the content. An idea hit me when I saw Mark Lorch’s revamping of the periodic table to mimic an underground rail system.

We’re all familiar with the most common depiction of the periodic table because it’s hanging in every chemistry classroom on the planet. Yet, there is no inherent physical reason we have to map the elements in that particular way. The underlying motive for this common form is to show the periodic nature of the properties of atoms as defined by their number of protons. But there are many possible ways to fulfill that goal. Non-traditional periodic tables can provide a new perspective on the relationships between atoms that are not obvious in the traditional drawing.

With that concept in mind, I decided to ask my students to rethink the Jablonski diagram.

The exact wording of the assignment was to “draw a Jablonski diagram that includes singlet and triplet excited states.” I was hoping to inspire some creativity so I pointed to the periodic table on the wall and then showed them a number of non-traditional periodic tables. I even said, “If you can express the nuances of the Jablonski Diagram through interpretive dance I would love to see it.”

No one choreographed a dance, but I was still blown away by my students’ response to the assignment. Below are some of their awesome creations.

Here is one, by Tian Zhao, depicting the lowest energy species on top and increasing energy as you go down. I like to think that it is expressing the cyclic nature of the excitation/relaxation process under steady-state conditions.

Picture1

This next submission, by Hadi Fares, is similar to the Bohr model of atoms and their electron orbitals that show the lowest energy state at the center and energy increasing outward. Unfortunately, this static image does not do justice to the animations he incorporated into the diagram.

Second image

This next diagram is similar to the one above but with additional artistic flare involving negative space. This aesthetic was inspired by “Vortex”, a game that Peilu Liu played on her ipod. The image got me thinking about the nodal planes of an orbital and whether or not it possible to graphically depict the likelihood of an electronic transition based on a comparison between the valence orbitals of a given state. Picture2

This final drawing, by Daniel Nascimento, really bumps up the information density of the Jablonski Diagram by not only including the energies of states and their transitions but also the approximate timescales of the events as shown on the x axis.

Jablonski

Much to my delight, a few students decided to really take a leap from tradition and make physical models of the Jablonski Diagram. Here is an ~12” tall work of art that was made by Maxime Matras out of aluminum rings—denoting the states (S0, T1, S1 and S2 from bottom to top)—and wires to denote the transitions between states (aluminum = excitation; copper = intersystem crossing, internal conversion, fluorescence and phosphorescence; coiled shavings = non-radiative decay).  This one now sits on my desk.

IMG_1655 small

 I even received a Jablonski diagram cake. The ground state, first singlet, second singlet and first triplet excited states are depicted in quadrants going clockwise (indicated by candy letters/numbers). The transitions are various colored lines of decorative frosting. What is really clever about this model is that the energy of the states are defined by their height from the pan. That is, the ground state is just a layer of chocolate frosting, the first excited state is a single layer of cake, and the second excited state is two layers. He also made the cake with tonic water in an effort to have it glow under a UV light. Unfortunately, I fear the cooking process destroyed the quinine and with it any possibility of glowing.  While not necessarily the most delicious of cakes, it was very creative.

 Cake image

And, finally, is “Jablinko!” This Jablonski diagram is based on the Japanese arcade and/or gambling game known as Pachinko. This photophysics-based game begins by placing a small metal ball into the S0 hole just above the lever. Pulling the lever, or exciting the molecule, shoots a ball to the top of the board into the singlet excited state. The ball (excited state) can fall one of three possible directions, NRD (non-radiative decay), ISC (intersystem crossing) or fluorescence. If it undergoes ISC, the ball can then fall into a potential well representing either non-radiative decay or phosphorescence from the triplet excited state. To top it all off, when the ball falls in to the fluorescence or phosphorescence holes it closes an electrical circuit that turns on a blue or red LED below the potential well. Those colors are the emission wavelengths for fluorescence and phosphorescence from anthracene.

Jablinko

In closing, I’d like to send a special thanks to my students. I have thoroughly enjoyed our time together and will always remember their clever responses to my first assignment.

By November 9, 2013 13 comments chemical education, fun