Dynamically weighted multiconfiguration self-consistent field: multistate calculations for F+H2O-->HF+OH reaction paths.
A novel method of dynamically adjusted weighting factors in state-averaged multiconfiguration self-consistent-field calculations (SA-MCSCF) is described that is applicable to systems of arbitrary dimensionality. The proposed dynamically weighted approach automatically weights the relevant electronic states in each region of the potential energy surface, smoothly adjusting between these regions with an energy dependent functional. This method is tested on the F(2P)+H2O-->HF+OH(2Pi) reaction, which otherwise proves challenging to describe with traditional SA-MCSCF methods due to (i) different asymptotic degeneracies of reactant (threefold) and product (twofold) channels, and (ii) presence of low-lying charge transfer configurations near the transition state region. The smoothly varying wave functions obtained by dynamically weighted multiconfigurational self-consistent field represent excellent reference states for high-level multireference configuration interaction calculations and offer an ideal starting point for construction of multiple state potential energy surfaces.
Deskevich
Michael P
MP
JILA, University of Colorado and National Institute of Standards and Technology, Boulder Colorado 80309-0440, USA.
Nesbitt
David J
DJ
Werner
Hans-Joachim
HJ