Particleparticle ladder based basisset corrections applied to atoms and molecules using coupledcluster theory
Abstract
We investigate the basisset convergence of electronic correlation energies calculated using coupled cluster theory and a recently proposed finite basisset correction technique. The correction is applied to atomic and molecular systems and is based on a diagrammatically decomposed coupled cluster singles and doubles (CCSD) correlation energy. Only the secondorder energy and the particleparticle ladder term are corrected for their basisset incompleteness error. We present absolute correlation energies and results for a large benchmark set. Our findings indicate that basis set reductions by two cardinal numbers are possible for atomization energies, ionization potentials, and electron affinities without compromising accuracy when compared to conventional CCSD calculations. In the case of reaction energies, we find that reductions by one cardinal number are possible compared to conventional CCSD calculations. The employed technique can readily be applied to other manyelectron theories without the need for three or fourelectron integrals.
 Publication:

Journal of Chemical Physics
 Pub Date:
 September 2019
 DOI:
 10.1063/1.5110885
 arXiv:
 arXiv:1903.05559
 Bibcode:
 2019JChPh.151j4107I
 Keywords:

 Physics  Chemical Physics;
 Condensed Matter  Materials Science;
 Physics  Atomic Physics;
 Physics  Computational Physics
 EPrint:
 9 pages, 3 figures, 6 tables