Explicit correlation and long range interactions

Joseph Lane
Department of Chemistry, University of Waikato, Hamilton, Nouvelle-Zélande
Jeudi 22 Novembre 2012, 14h00
bibliothèque LCT, tour 12 - 13, 4e étage

The painfully slow convergence of electron correlation energy with increasing basis set size is considered one of the great challenges in modern computational chemistry. In the last few years, significant advancements have been made to accelerate this convergence by including a small number of terms to the wavefunction that depend explicitly on the interelectronic distance. We have benchmarked the performance of the explicitly correlated CCSD(T)-F12 method and compare results to those obtained with conventional CCSD(T). We have calculated optimized geometries and interaction energies for a series of hydrogen bonded and more general van der Waals complexes. Overall, we find that results obtained with the CCSD(T)-F12 method are impressive and more than compensate for the additional computational expense compared to conventional CCSD(T). We have used the CCSD(T)-F12 method to investigate cooperative intermolecular interactions for a series of CO2 complexes to facilitate a more rational design of CO2 capture materials.