+ Site Statistics

+ Search Articles

+ Subscribe to Site Feeds

Most Shared

PDF Full Text

+ PDF Full Text

Request PDF Full Text

+ Follow Us

Follow on Facebook

Follow on Twitter

Follow on LinkedIn

+ Translate

+ Recently Requested

Analytical State-Average Complete-Active-Space Self-Consistent Field Nonadiabatic Coupling Vectors: Implementation with Density-Fitted Two-Electron Integrals and Application to Conical Intersections

Fdez Galván, I.; Delcey, Mël.G.; Pedersen, T.Bondo.; Aquilante, F.; Lindh, R.

Journal of Chemical Theory and Computation 12(8): 3636-3653

2016

Analytical state-average complete-active-space self-consistent field derivative (nonadiabatic) coupling vectors are implemented. Existing formulations are modified such that the implementation is compatible with Cholesky-based density fitting of two-electron integrals, which results in efficient calculations especially with large basis sets. Using analytical nonadiabatic coupling vectors, the optimization of conical intersections is implemented within the projected constrained optimization method. The standard description and characterization of conical intersections is reviewed and clarified, and a practical and unambiguous system for their classification and interpretation is put forward. These new tools are subsequently tested and benchmarked for 19 different conical intersections. The accuracy of the derivative coupling vectors is validated, and the information that can be drawn from the proposed characterization is discussed, demonstrating its usefulness.

Related references