Pseudospectral generalized valencehyphen;bond calculations: Application to methylene, ethylene, and silylene

摘要

The pseudospectral (PS) method for selfhyphen;consistenthyphen;field calculations is extended for use in generalized valencehyphen;bond calculations and is used to calculate singletndash;triplet excitation energies in methylene, silylene, and ethylene molecules and bond dissociation and twisting energies in ethylene. We find that the PS calculations lead to an accuracy in total energies of le;0.1 kcal/mol and excitation energies to le;0.01 kcal/mol for all systems. With effective core potentials on Si, we find greatly improved accuracy for PS.