Fast vibrational self-consistent field calculations through a reduced mode-mode coupling scheme.
We present a new methodology to perform fast correlation-corrected vibrational self-consistent field (CC-VSCF) calculations using ab initio potential energy points calculated on the fly. Our method is based on the replacement of all-electron basis sets with a pseudo-potential basis for heavy atoms, and on an efficient reduction of the number of pair-coupling elements used in the CC-VSCF procedure. The method is applied to several test systems: H2O, NH3, and CH4, where it proves to be efficient, providing a speedup factor of 2 compared to a standard CC-VSCF calculation. We also apply our technique to the simulation of the vibrational spectrum of ethane and show that very accurate results can be obtained with a substantial speedup for this system.
Department of Chemistry, Queen Mary, University of London, Mile End Road, London, E1 4NS, United Kingdom. d.m.benoit@ucl.ac.uk
David M
DM
Benoit
D000465:Algorithms; D000641:Ammonia / Q000737:chemistry*; D001704:Biopolymers / Q000737:chemistry*; D003198:Computer Simulation; D008697:Methane / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D015233:Models, Statistical; D014732:Vibration; D014867:Water / Q000737:chemistry*
D001704:Biopolymers; D014867:Water; D000641:Ammonia; D008697:Methane