aspuru-list January 2015

aspuru-list@lists.fas.harvard.edu

23 participants
43 discussions

[Aspuru-Guzik group list] Fwd: quick VASP question

by Sawaya, Nicolas

Hi Marlon and Cynthia, There is no rush, but when possible would you guys mind sending an email to vasp.materialphysik(a)univie.ac.at<mailto:vasp.materialphysik@univie.ac.at>, requesting that I be added to the license? (see below) Let me know if you need anything from me. Thanks! Nicolas Begin forwarded message: From: Suleyman Er <suleymaner(a)gmail.com<mailto:suleymaner@gmail.com>> Subject: Re: quick VASP question Date: January 18, 2015 at 8:35:29 AM EST To: "Sawaya, Nicolas" <nicolassawaya(a)fas.harvard.edu<mailto:nicolassawaya@fas.harvard.edu>> Hi Nicolas, I am at Leiden University, the Netherlands. To be added to the users list. If Alan's already approved you should ask Marlon (or Cynthia) to send an email to: vasp.materialphysik(a)univie.ac.at<mailto:vasp.materialphysik@univie.ac.at> The most current user list is Alan, Suleyman, Semion, Xavier, Martin, and Chris. I think Xavier and Chris are safe to be removed from the list since there is a maximum limit for the number of users from a research group. I attached a copy of license below to this email. Good luck! -Suleyman On Jan 17, 2015, at 2:27 AM, Sawaya, Nicolas wrote: > Actually, more importantly, I'm wondering these things: > 1. How can I get added to Alan's VASP license? > 2. Do you happen to know what the license number is, or how I can find it? > > I know you've partially moved on to a different group--I hope things are going well so far! (Where did you move to, actually?) > > Cheers, Nicolas > > On Jan 16, 2015, at 7:57 PM, Nicolas Sawaya <nicolassawaya(a)fas.harvard.edu<mailto:nicolassawaya@fas.harvard.edu>> wrote: > >> Hey Suleyman, >> I know you've run VASP before for a previous paper, and I'm wondering where you ran it. On your own computer for perhaps on an XSede server? I'm trying to interface with an NVIDIA employee who will make me a beta tester for the software. >> >> Cheers, >> Nicolas >

9 years, 3 months

[Aspuru-Guzik group list] Dinner / Drinks at Cambridge Commons?

by Alan Aspuru-Guzik

Dear group members, If anybody is interested, as I said early in the group meeting, some of us will be at Cambridge commons for dinner/drinks starting at 6. Let me know if you are interested. I would be leaving my office at around 5.40 if anybody wants to walk there with me, Looking forward to an impromptu group gathering of those who can make it :) Best, A. Alán Aspuru-Guzik | Professor of Chemistry and Chemical Biology Harvard University | 12 Oxford Street, Room M113 | Cambridge, MA 02138 (617)-384-8188 | http://aspuru.chem.harvard.edu | http://about.me/aspuru

9 years, 3 months

[Aspuru-Guzik group list] Excitonics Seminar, TODAY, Jan 15, 3:30 pm/ 4-270

by Catherine M Bourgeois

TODAY _______ CENTER FOR EXCITONICS SEMINAR "Non-contact Nondestructive Probing of Charge Carrier Conductivity in Organic Materials and their Interfaces" January 15, 2015 at 3:30pm/ 4-270 Shu Seki, Osaka University [seki_01] Abstract: Understanding charge carrier transport processes at interfaces is one of the most important subjects in organic electronics. Charge carriers are injected or extracted through metal/semiconductor interfaces in most electronic devices, while carrier transport occurs at insulator/semiconductor interfaces rather than in the bulk in the major organic electronic devices.1,2 However, analytical techniques for evaluating such interfacial carrier transport phenomena are still limited, and this remains a challenging issue. We have recently reported a technique, referred to as time-resolved microwave conductivity (TRMC)3, and the system has been extended into field-induced TRMC that combines charge carrier injection via gate bias applied into working devices and microwave-based non-contact probing of intrinsic and local charge carrier motion. The schematic diagram of the set of apparatus is given in figure 1. Using this technique, it was determined that a Au/pentacene/PMMA/SiO2/Au MIS device had hole and electron mobilities of 6.3 and 0.3 cm2V-1s-1, respectively.4,5 Non-contact, fully experimental evaluation of intra-domain carrier mobility at interfaces is quite unprecedented and is a characteristic feature of this system. In this paper, we further report that the FI-TRMC technique can distinguish between mobile charge carriers at the interface and immobile charges trapped at defects, thus enabling quantification of both the charge carrier mobility and the density of trap sites at insulator-semiconductor interfaces, and discuss also on the extraordinary mobile charge carriers at the interfaces on highly developed planner *-conjugated systems such as graphene and its derivatives. References: 1) G. Horowitz and P. Delannoy, J. Appl. Phys. 70, 469 (1991). 2) H. Klauk, Chem. Soc. Rev. 39, 2643 (2010). 3) S. Seki, et al., Phys. Chem. Chem. Phys. 16, 11093 (2014); Acc. Chem. Res. 45, 1193 (2012); Nature Commun. 5, 3718 (2014); Nature Commun. 4, 2694 (2013); Nature Commun. 4, 1691 (2013); 4) S. Seki, et al., Sci. Rep. 3, 3182 (2013). 5) W. Choi, T. Miyakai, T. Sakurai, A. Saeki, M. Yokoyama, S. Seki, Appl. Phys. Lett. 105, 019430 (2014) Bio: Shushi Seki received his BS (1991) and MS (1993) in Engineering at the University of Tokyo. In 1995, he worked in the Chemistry Division at the Argonne National Laboratory . He was Assistant Professor at Osaka University, Japan, from 1995 - 2001 while earning his PhD in 2001. From 2001 - 2007, he was an Associate Professor at the Institute of Scientific and Industrial Research and from 2007-2009, at the Department of Applied Chemistry, both at Osaka University. Currently, he is Professor in the Department of Applied Chemistry Graduate School of Engineering at Osaka and his area of research is in condensed matter physical chemistry. Light refreshments will be served The Center For Excitonics Is An Energy Frontier Research Center Funded By The U.S. Department Of Energy, Office Of Science And Office Of Basic Energy Sciences

9 years, 3 months

[Aspuru-Guzik group list] ITAMP lunch seminar - Special Triple Features: B. Lee, S. Markson, and D. Marshall (ITAMP)

by Richard Schmidt

Dear colleagues, this week we have a special ITAMP seminar: In a triple feature the students working at ITAMP will give short talks introducing us to their research. Kind regards, Richard and Swati ITAMP Topical Lunch Discussion - Special triple feature Date: Friday, January 16th Time: 12:00-1:30 pm Pizza will be served. Location: B-106 @ Center for Astrophysics (60 Garden Street) Directions: after entering the lobby of the CfA, turn right to enter the hallway of the B building. In the hallway, turn right again, and B-106 is there. Speaker: Bill Lee, ITAMP Title: A glimpse into the novel master equation formalism to describe superradiance with the driving electric field Abstract: Developments and difficulties arisen in the recently developed method to describe superradiance with the external driving field. I will discuss some special techniques such as Schwinger-Keldysh contour, cumulant expansion, and Dyson equation applied in finding the time evolution of superradiance decay rate, as well as the validity of some important approximations. Speaker: David W. Marshall, ITAMP Title: Simulations of dynamics of carbon-rich molecules on surfaces Abstract: Not only has mid-IR imaging revealed an extraordinary variety of carbon-rich molecules present in galaxies, but also that they can be seen in a host of different astronomical bodies; from HII regions to planetary nebula, and from young stellar objects to old post-AGB sources. The range of organic species discovered so far include PAHs, fullerenes, long chain hydrocarbons and carbonaceous dust grains, some of which are biologically important. There is strong evidence that much of the terrestrial water was delivered to Earth during the Late Heavy Bombardment (LHB) approximately 3.8 - 4.1 Gyr ago. Comparisons of the deuterium-hydrogen ratio of the Vienna Mean Standard Ocean Water and comets like Hartley 2, have revealed a striking similarity. It's not without reason to assume that prebiotic molecules may have been delivered to Earth in a similar way. In this work, reactive molecular dynamics simulations are performed to probe the formation of carbon-rich molecules and clusters on graphitic surfaces. The simulations are run over a range of temperatures, densities and carbonaceous surfaces and a comparison is made of the distribution of chain and cluster formation in the gas and condensed phases. Speaker: Sam Markson, ITAMP Title: Pathways to heavy Rydberg states Abstract: We examine various ways in which the 2013 methods toward creating 'heavy rydberg states' in rubidium 87 may be optimized, along with describing various numerical algorithms useful in characterizing these states and their lifetimes. --------------------------- Dr. Richard Schmidt Institute for Theoretical Atomic, Molecular, and Optical Physics (ITAMP) Harvard-Smithsonian Center for Astrophysics MS-14 60 Garden St. Cambridge, MA 02138 U.S.A. richard.schmidt(a)cfa.harvard.edu Tel. +1 (617) 496-7610 Fax +1 (617) 496-7668

9 years, 3 months

[Aspuru-Guzik group list] [Aspuru-meetings-list] Group Meeting tomorrow, 2:30pm Div Room

by Jennifer Wei

Hi everyone, Hope everyone had a good break. Tomorrow Taka will be giving group meeting in the Div room at 2:30pm. Please see below for his title and abstract. See you all there! Jennifer ------------------------------------------------ "How to separate an electron-hole pair? Toward a simulation of charge photogeneration" Organic solar cells have attracted widespread interest in recent years, yet, it is still controversial as to how exciton dissociates into free charge careers at a donor/acceptor interface. In this talk, I will present my recent work on simulating quantum dynamics of a charge photogeneration process. I will introduce a tight-binding Hamiltonian which can treatFrenkel exciton and charge-transfer states on the same footing and explain how to parameterize it from quantum-chemistry calculations. I will then show preliminary results on dinaphtho[2,3-b:2'3'-f]thieno[3,3-b]-thiophene (DNTT), p-type organic semiconductor. Combing with a stochastic Schrodinger equation, the model is applied to study relaxation dynamics of a charge-transfer state in the DNTT cluster. Finally, I will discuss a next step to the DNTT crystal. _______________________________________________ Aspuru-meetings-list mailing list Aspuru-meetings-list(a)lists.fas.harvard.edu https://lists.fas.harvard.edu/mailman/listinfo/aspuru-meetings-list

9 years, 3 months

[Aspuru-Guzik group list] FW: Excitonics Seminar, TOMORROW, Jan 15, 3:30 pm/ 4-270

by Catherine M Bourgeois

Please post and forward to your groups ________ CENTER FOR EXCITONICS SEMINAR "Non-contact Nondestructive Probing of Charge Carrier Conductivity in Organic Materials and their Interfaces" January 15, 2015 at 3:30pm/ 4-270 Shu Seki, Osaka University [seki_01] Abstract: Understanding charge carrier transport processes at interfaces is one of the most important subjects in organic electronics. Charge carriers are injected or extracted through metal/semiconductor interfaces in most electronic devices, while carrier transport occurs at insulator/semiconductor interfaces rather than in the bulk in the major organic electronic devices.1,2 However, analytical techniques for evaluating such interfacial carrier transport phenomena are still limited, and this remains a challenging issue. We have recently reported a technique, referred to as time-resolved microwave conductivity (TRMC)3, and the system has been extended into field-induced TRMC that combines charge carrier injection via gate bias applied into working devices and microwave-based non-contact probing of intrinsic and local charge carrier motion. The schematic diagram of the set of apparatus is given in figure 1. Using this technique, it was determined that a Au/pentacene/PMMA/SiO2/Au MIS device had hole and electron mobilities of 6.3 and 0.3 cm2V-1s-1, respectively.4,5 Non-contact, fully experimental evaluation of intra-domain carrier mobility at interfaces is quite unprecedented and is a characteristic feature of this system. In this paper, we further report that the FI-TRMC technique can distinguish between mobile charge carriers at the interface and immobile charges trapped at defects, thus enabling quantification of both the charge carrier mobility and the density of trap sites at insulator-semiconductor interfaces, and discuss also on the extraordinary mobile charge carriers at the interfaces on highly developed planner *-conjugated systems such as graphene and its derivatives. References: 1) G. Horowitz and P. Delannoy, J. Appl. Phys. 70, 469 (1991). 2) H. Klauk, Chem. Soc. Rev. 39, 2643 (2010). 3) S. Seki, et al., Phys. Chem. Chem. Phys. 16, 11093 (2014); Acc. Chem. Res. 45, 1193 (2012); Nature Commun. 5, 3718 (2014); Nature Commun. 4, 2694 (2013); Nature Commun. 4, 1691 (2013); 4) S. Seki, et al., Sci. Rep. 3, 3182 (2013). 5) W. Choi, T. Miyakai, T. Sakurai, A. Saeki, M. Yokoyama, S. Seki, Appl. Phys. Lett. 105, 019430 (2014) Bio: Shushi Seki received his BS (1991) and MS (1993) in Engineering at the University of Tokyo. In 1995, he worked in the Chemistry Division at the Argonne National Laboratory . He was Assistant Professor at Osaka University, Japan, from 1995 - 2001 while earning his PhD in 2001. From 2001 - 2007, he was an Associate Professor at the Institute of Scientific and Industrial Research and from 2007-2009, at the Department of Applied Chemistry, both at Osaka University. Currently, he is Professor in the Department of Applied Chemistry Graduate School of Engineering at Osaka and his area of research is in condensed matter physical chemistry. Light refreshments will be served The Center For Excitonics Is An Energy Frontier Research Center Funded By The U.S. Department Of Energy, Office Of Science And Office Of Basic Energy Sciences

9 years, 3 months

[Aspuru-Guzik group list] Excitonics Seminar, Jan 15, 3:30 pm/ 4-270

by Catherine M Bourgeois

9 years, 3 months

[Aspuru-Guzik group list] APS

by Alan Aspuru-Guzik

Dear all, Anybody that I approved for going to APS should e-mail Marlon today as I need to double-check who is actually going. Best, Alan Alán Aspuru-Guzik | Professor of Chemistry and Chemical Biology Harvard University | 12 Oxford Street, Room M113 | Cambridge, MA 02138 (617)-384-8188 | http://aspuru.chem.harvard.edu | http://about.me/aspuru

9 years, 3 months

[Aspuru-Guzik group list] Fwd: Next CIQM Research Exchange Seminar: Wenjing Fang: January 14 12:00 noon.

by Marlon Cummings

*From: *Naomi Brave <brave(a)seas.harvard.edu> *Subject: **Next CIQM Research Exchange Seminar: Wenjing Fang: January 14 12:00 noon.* *Date: *January 9, 2015 12:11:50 PM EST *To: *CIQM All Participants, CIQM Students Participants, CIQM Students Affiliates *Bcc: *Wenjing Fang <wjfang(a)mit.edu>, Gilbert Cordova <gcordova(a)mit.edu>, Monica Wolf <mwolf(a)MIT.EDU> Dear CIQM Community, Our next Research Exchange Seminar will be: Wednesday, January 14 12:00-1:30 MIT Duboc 4-331 *Wenjing Fang* Kong Group, MIT *Synthesis of Graphene Films on Cu* *Enclosures with Layer Control* For those unable to attend in person, the Go To Meeting info is: - Please join my meeting from your computer, tablet or smartphone. https://global.gotomeeting.com/join/732261061 - You can also dial in using your phone. United States (Long distance): +1 (312) 757-3111 *Access Code:* 732-261-061 More phone numbers: https://global.gotomeeting.com/732261061/numbersdisplay.html -

9 years, 3 months

[Aspuru-Guzik group list] Post-doc candidate

by Edward Pyzer-Knapp

Hi all , Steven Lopez from the Houk group will be coming on the 4th Feb to give a talk as a potential post-doc here. His abstract is attached. If you are interested in meeting him could you drop me an email with some times that would suit. People with an interest in materials and molecular reactivity are strongly encouraged to schedule a meeting :) Ed **************************************************** Towards designing new reactions and materials: Using chemical computations to understand bioorthogonal reactivities and semiconducting efficiencies Steven A. Lopez First, I will discuss how DFT calculations have been used to understand the reactivities and stereoselectivities of 1,3-dipolar cycloadditions to norbornenes. Thesecycloadditions have recently found extensive use in bioorthogonal chemistry because they can efficiently and selectively label biomolecules without structural perturbation of the target. From these DFT studies, we have rationalized the origins of the mutuallyorthogonality of bioorthogonal reactions, and have discovered new mutually orthogonal bioorthogonal reactions. Next, I will discuss a methodology developed by our group to compute hole-mobilities of organic semiconducting materials based on a charge hopping mechanism. To compute hole-mobilities of (single) crystalline materials, we rely on Marcus Theory to determine hopping rates using a combination of DFT, semiempirical, and kinetic Monte Carlo calculations (to simulate charge-carrier dynamics). To determine the hole-mobilities of thin-film crystals, a MD simulation is used to “disorder” the single crystal structure to create a reasonable model of the thin film material. Site energies are calculated prior to the hopping rate calculation for hole-mobilities of thin film crystals. This methodology was recently applied to understand the relationship between structure and device performance of BTTT oligomers in OFETs in collaboration with the Briseño group. ᐧ

9 years, 3 months

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aspuru-list January 2015