### Speaker: Anil Damle, *Stanford*

Title: Sparse representations and fast algorithms for Kohn-Sham orbitals

Abstract: Kohn-Sham density functional theory is the most widely used electronic structure theory for molecules and systems in condensed phase. The Kohn-Sham orbitals (a.k.a. Kohn-Sham wavefunctions) are eigenfunctions of the Kohn-Sham Hamiltonian and are generally delocalized, i.e. each orbital has significant magnitude across the entire computational domain. Given a set of Kohn-Sham orbitals from an insulating system, it is often desirable to build a set of localized basis functions for the associated subspace. In this talk we present a simple, robust, and parallelizable algorithm to construct a set of (optionally orthogonal) localized basis functions known as the selected columns of the density matrix (SCDM). In addition, we will discuss recently developed variants of the SCDM algorithm that drastically reduce the computational cost while maintaining the quality of the basis.

Bio: Anile Damle is a PhD candidate in the Institute for Computational and Mathematical Engineering (ICME) at Stanford University. His general interests include numerical linear algebra, non-linear approximations, matrix analysis, and fast algorithms for structured matrices. Anil's current research projects focus on localization of Kohn-Sham orbitals, updating of certain tree based matrix factorizations, and non-negative matrix factorizations. Visit Anil's personal webpage at: http://web.stanford.edu/~damle/

Location:

Y2E2-101

Organizer:

Michael Saunders

Date:

Thursday, April 21, 2016 -

4:30pm to 5:45pm