Samuel B. Trickey

Personal Information
  • Professor of Physics and Chemistry (emeritus June 2005)
  • Former Director QTP (1999-2004)
  • Email address: trickey at qtp.ufl.edu
  • Office: 2324 New Physics Building
  • Phone: 352-392-1597
  • Fax: 352-392-8722

NEW! We seek four Postdocs. The Dept. of Energy has funded our new project on orbital-free free-energy density functional theory for warm dense matter. Here is the link to the pdf file for the ad. Also see research summaries below.

Research Interests

Density Functional Theory (DFT)

I work on both DFT, and to some extent, Current DFT (CDFT).

A new (Sept. 2009) Dept. of Energy project is development of orbital-free free-energy density functionals. Target physical systems are in the Warm Dense Matter regime: systems with electron temperatures of order 10 electron volts at solid densities. My co-PIs are Jim Dufty, Frank Harris, and Keith Runge. This is an outgrowth of zero-temprature work with Valentin Karasiev (IVIC, Venezuela) and Frank Harris on developing orbital-free approximations to the Kohn-Sham kinetic energy to use in calculating Born-Oppenheimer forces in fast molecular dynamics simulations. See references below

With Klaus Capelle and Mariana Odashima (IFSC, U. Sao Paulo, Brazil), I have been studying the effects of altering the enforcement of the Lieb-Oxford bound in generalized gradient approximation exchange-correlation functionals. See the 2009 J. Chem. Theory and Comput. paper cited below; there is more to come.

With Alberto Vela and Victor Medel (Cinvestav, Mexico City), I have been developing a modifed generalized gradient approximation exchange- correlation functional which improves on PBE GGA by about 20 percent in atomization energies of diatomics. See the 2009 J.Chem. Phys. paper below; there is more to come.

Wuming Zhu (Ph.D. August 2005) and I did an exhaustive study of CDFT and ordinary DFT in large external B fields, including exact Hooke's atom solutions. See the Phys. Rev. A paper and J. Chem. Phys. papers cited below. There is still more to be written up.

Development of Algorithms for Predictive Simulations of Materials

PUPIL (Program for User Package Interfacing and Linking) is an open-source JAVA, CORBA, and XML-based system for interoperating user application packages (e.g. electronic structure, molecular dynamics, domain identifiers) as a systematic multi-scale modeling tool. Begun under the NSF ITR-medium award (DMR-0325553), work continues on developing PUPIL. The development leadership group is Joan Torras Costa, Erik Deumens, Gustavo Seabra, Ben Roberts, and I. See the PUPIL papers listed below and the project link .

Methods for detailed DFT calculations on materials are developed in close collaboration with Jon Boettger (LANL), the principal author of the code GTOFF (that originated here). A review article is listed below.

I also work on adding features and functionality to the deMon2k molecular, gaussian basis DFT code, in cooperation with the development group at Cinvestav, Mexico City. The deMon2k home page is here .

Predictive Calculation of

  • structures and properties of Ultra-thin Films and counterpart crystals, with emphasis on surface effects related to chemical bonding in cracking, quantum size effects, energy deposition by charged particles, and high magnetic field effects.
  • high-pressure and/or high-temperature behavior of condensed systems, with emphasis on structural phase transitions, warm dense matter (temperatures of order 10 eV), as well as calibration of embedding potentials for Molecular Dynamics in multi-scale simulations.
Current computational effort is on effects of new DFT functionals (see above) upon the predicted structure and properties of simple ultra-thin films and their counterpart crystals. Fairly recently, Jon Boettger (LANL) and I calculated spin-orbit splitting in graphene (see below).  

Representative Publications
  • Variable Lieb-Oxford Bound Satisfaction in a Generalized Gradient Exchange-Correlation Functional, A. Vela, V. Medel and S. B.Trickey, J. Chem. Phys. 130, 244103 [6 pp] (2009).
  • Tightened Lieb-Oxford Bound for Systems of Fixed Particle Number, M.M. Odashima, K. Capelle, and S.B.Trickey, J. Chem. Theory and Comput. 5, 798-807 (2009).
  • A Versatile AMBER-Gaussian QM/MM Interface Through PUPIL, J. Torras, G. de M. Seabra, E. Deumens, S.B. Trickey, and A.E. Roitberg, J. Comput. Chem. 29, 1564-1573 (2008).
  • PUPIL: A Systematic Approach to Software Integration in Multi-scale Simulations , J. Torras, Y. He, C. Cao, K. Muralidharan, E. Deumens, H-P. Cheng, and S.B. Trickey, Computer Phys. Commun. 177, 265-79 (2007).
  • First Principles Calculation of Spin-orbit Splitting in Graphene , J.C. Boettger and S.B.Trickey, Phys. Rev. B 75, 121402(R) [3 pp] (2007); erratum Phys. Rev. B 75, 199903 (2007). .
  • Born-Oppenheimer Interatomic Forces from Simple, Local Kinetic Energy Density Functionals, V.V. Karasiev, S.B.Trickey, and F.E. Harris, J. Computer-Aided Mat. Design, 13, 111-129 (2006).
  • Exact Density Functionals for Two-electron Systems in an External Magnetic Field , Wuming Zhu and S.B. Trickey, J. Chem. Phys. 125, 094317 [12 pp] (2006).
  • Analytical Solutions for Two Electrons in an Oscillator Potential and a Magnetic Field, Wuming Zhu and S. B.Trickey, Phys. Rev. A 72, 022501 [5 pp] (2005).
  • Methods and Implementation of Robust, High-precision Gaussian Basis DFT Calculations for Periodic Systems: the GTOFF Code, S. B. Trickey, J. A. Alford, and J. C. Boettger, in Computational Materials Science, vol. 15 of "Theoretical and Computational Chemistry", J.Leszczynski ed. (Elsevier, Amsterdam, 2004) 171-228.
  • State Energy Functionals and Variational Equations in Density Functional Theory, B. Weiner and S. B. Trickey, J. Molec. Struct. (Theochem) 501-02, 65-83 (2000).
  • A Critical Assessment of Density Functional Theory with Regard to Applications in Organometallic Chemistry, A. Görling, S.B. Trickey, P. Gisdakis, and N. Rösch, in Topics in Organometallic Chemistry, vol. 4, P. Hofmann and J.M. Brown, Eds. (Springer Verlag, Heidelberg, 1999) 109-63.
Click here for a more extensive list of Publications.

Recent Invited Lectures

  • Reworking the Second Rung of the Exchange-Correlation Ladder, Symposium on Density Functional Methods and Their Applications, Geburtstagfest für Prof. N. Rösch, Technische Universität München, 7 Nov. 2008.
  • Tightening the Lieb-Oxford Bound in the PBE Exchange-Correlation Functional , Simposio de Teoría de Funcionales de la Densidad, Univ. Autónoma Metropolitana -- Iztapalapa, México City, México, 17 October 2008.
  • Física de Música y Música de Física, (in Spanish) Escuela de Laudería, Instituto Nacionál de Bellas Artes de México, Querétaro, Querétaro, México, 14 October 2008.
  • Short Course on Density Functional Theory and Applications , 10 lectures, Dept. of Physics, Michigan Technological University, Houghton Michigan, Sept. 15--19, 2008.
  • Recent Progress on Orbital-free Kinetic Energy Density Functionals for Materials Simulations , Sixth Congress of the Internat. Soc. for Theoretical Chemical Physics, Vancouver B.C., 24 July 2008
  • Stress, Fracture, and Hydrolytic Effects in Nanoscale Silica Systems , CECAM Workshop on Modelling the Structure and Reactivity of Silica and Water, Lyon France, Sept. 17-19, 2007.
  • Prediction of Materials Properties via Local Basis Set DFT Methods ,Pan American Advanced Scientific Institute on Electronic States and Excitations in Nanostructures, Zacatecas México, June 11-15, 2007.

Chile Click here for 2005 visit to Chile.
Here's the link to National Farm Worker Ministry, a long-time personal commitment.
Here's the link to the Gainesville sailing club
Here's a link to the boat on Lake Superior on which I crew

Last modified 03 Sept. 2009