Detailed Pair Natural Orbital-Based Coupled Cluster Studies of Spin Crossover Energetics.

ABSTRACT: In this work, a detailed study of spin-state splittings in three spin crossover model compounds with DLPNO-CCSD(T) is presented. The performance in comparison to canonical CCSD(T) is assessed in detail. It was found that spin-state splittings with chemical accuracy, compared to the canonical results, are achieved when the full iterative triples (T₁) scheme and TightPNO settings are applied and relativistic effects are taken into account. Having established the level of accuracy that can be reached relative to the canonical results, we have undertaken a detailed basis set study in the second part of the study. The slow convergence of the results of correlated calculations with respect to basis set extension is particularly acute for spin-state splittings for reasons discussed in

SUBMITTER: Floser BM 

PROVIDER: S-EPMC7310951 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature