Interatomic Potentials from Permutation-Invariant Polynomials
13th. Nov. 2019, ICAMS Special Seminar, IC 02-718, ICAMS, Ruhr-Universität Bochum
Time:
Start: 13th. Nov. 2019. 01:00 p.m.
End: 13th. Nov. 2019. 02:00 p.m.
Author(s):
Professor Christoph Ortner University of Warwick, Mathematics Institute, Coventry, UK
Organizer(s):
Professor Ralf Drautz ICAMS, Ruhr-Universität Bochum
Abstract:
I will present the construction of interatomic potentials for materials and molecules
based on a body-order expansion (ANOVA, HDRM, cluster expansion), each body order being represented by polynomials satisfying the rotation and permutation symmetry of the "exact" PES. These polynomials are determined in a data-driven fashion from linear fits trained with ab initio data. The two main issues I will discuss are (1) convergence "in theory" as well as on training sets; (2) regularisation and generalisation.
Joint work with Alice Allen (Cambridge), Gábor Csányi (Cambridge), Christoph Ortner
(Warwick), and Cas van der Oord (Cambridge).