Implicit solvation in domain based pair natural orbital coupled cluster ( <scp>DLPNO‐CCSD</scp> ) theory

A nearly linear scaling implementation of coupled-cluster with singles and doubles excitations (CCSD) can be achieved by means the domain-based local pair natural orbital (DLPNO) method. The combination DLPNO-CCSD implicit solvation methods allows calculation accurate energies chemical properties solvated systems at an affordable computational cost. We have efficiently implemented different schemes within conductor-like polarizable continuum model (C-PCM) for in ORCA quantum chemistry suite. In our implementation, overhead due to additional solvent terms amounts less than 5% time equivalent gas phase job takes. Our results organic neutrals open-shell ions water show that most systems, adding amplitudes equations energy leads small changes total compared only considering orbitals corrections reference energy. However, when solute contains certain functional groups, such as carbonyl or nitrile are larger estimated around 0.04 0.02 kcal/mol each group solute, respectively. For solutes containing metals, use CC/C-PCM is crucial account correlation effects. Simultaneously, we calculated electrostatic component DLPNO-CCSD/C-PCM schemes. observe negligible deviation between canonical-CCSD data. Here, outperform those Hartree-Fock density theory calculations.