This web site is kept mostly for historical reasons and updated only occasionally. To keep up with our research progress on free-energy density functional theory (DFT) and orbital-free DFT, please go to the project website .
Personal Information
13 May 2020: We have a new postdoc position available. Go to the project website for further information. |
Research Interests
Center for Molecular Magnetic Quantum Materials
I am a co-PI in the Center, working mostly on algorithms and on spin-crossover molecules and assemblies of them. Much more information is available from the the Center website .
Density Functional Theory
I work on DFT, both ground state and free-energy (finite temperature) versions, and to some extent on Current DFT (CDFT).
Since Sept. 2009, we have had a major Dept. of Energy project for development of orbital-free free-energy density functionals. Target physical systems are in the Warm Dense Matter regime: typical electron temperatures are of order 10 electron volts yet at condensed-phase densities. The original co-PIs were Jim Dufty, Frank Harris, and Keith Runge. The project is a major development of earlier zero-temprature work with Valentin Karasiev (formerly of IVIC, Venezuela, now Lab. for Laser Energetics, Univ. of Rochester) 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
Recently (May 2020) I received a National Science Foundation grant with Antonio Cancio, Ball State Univ as co-PI, for "Pure Density Functionals for Efficient, Predictive Simulations". It is a follow-on to success with a NSF EAGER grant "Rung-reduced Density Functionals for Cost-capped ab initio Molecular Dynamics" which demonstrated the concept of de-orbitalization of metaGGA exchange-correlation functionals.
That work is closely related to the continuting collaboration with Alberto Vela ( Cinvestav, Mexico City) and José Luis Gázquez (UAM-I, Mexico City) and their associates, notably Javier Carmona Espíndola at UAM-I. We have been pushing the limits of the lower rungs of the Perdew-Schmidt "Jacob's ladder" of exchange- correlation functionals. Publications for the last decade are at the Publications page of my group's web site.
Wuming Zhu (Ph.D. August 2005) and I from time to time work on Current DFT. We introduced a self-interaction-free ordinary DFT treatment of atoms in large external B fields. Remarkably, current DFT isn't needed. See the Phys. Rev. A 90 paper listed in the publications or get it from Publications
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), development now is with
Joan Torras Costa. Earlier the development group was Joan, Erik Deumens, Gustavo Seabra, Ben Roberts, and I.
There is a bio-molecular oriented review cited in the publication list below. Also see the
project link .
Gaussian-basis, all-electron methods and
algorithm for detailed DFT calculations on materials were
developed in close collaboration with Jon Boettger (LANL, now retired),
the principal author of the code GTOFF (that originated here). A
review article is listed below.
For several years I also worked 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 . For lack of time I have not done that recently.
Invited Lectures - an Older Sample
Last modified 31 May 2020