New ’Low-Cost’ Electronic Structure Methods for Large Systems
- TH Department Online Seminar
- Date: Mar 16, 2023
- Time: 03:00 PM (Local Time Germany)
- Speaker: Prof. Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Clausius Institute for Physical and Theoretical Chemistry, University of Bonn, Germany
- Location: https://zoom.us/j/97106685817?pwd=U1RlRXRwWDd1aWRlQlgwRURqVzRKdz09
- Room: Meeting ID: 971 0668 5817 | Passcode: 282712
- Host: TH Department
Recently, we proposed a new special purpose tight-binding (TB) electronic Hamiltonian termed PTB which is expressed in an accurate polarized valence double-zeta AO basis set (vDZP). The basis has been specially optimized in molecular DFT calculations using standard ECPs for all elements up to radon. The PTB method aims primarily at reproducing the one-particle density matrix of a DFT reference calculation with the ωB97X-V range-separated hybrid density functional in exactly the same AO basis. The combination of ωB97X(-V) with vDZP/ECP and an adjusted D4 dispersion correction deﬁnes a new member in our hierarchy of eﬃcient composite electronic structure methods, termed ωB97X-3c and is used as reference. The PTB procedure is non-self-consistent employing only two matrix diagonalizations, includes new non-local potentials, as well as established parts from GFN-xTB and requires only simple overlap integrals as input. Compared to ωB97X-3c calculations, speedups of 3-4 orders of magnitude are achieved so that runs for molecules with 100-200 atoms are completed in a few seconds of computation time on standard desktop computers. The use of the PTB density in typical computational chemistry applications as well as for non-SCF-iterative DFT-GGA schemes is discussed.
 S. Grimme, M. Müller, A. Hansen, J. Chem. Phys., DOI: 10.1063/5.0137838.
 M. Müller, A. Hansen, S. Grimme, J. Chem. Phys. 158 (2023) 014103.
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