Local correlation domains for coupled cluster theory: optical rotation and magnetic-field perturbations.
An approach is described for selecting local-correlation orbital domains appropriate for computing response properties such as optical rotation using frequency-dependent coupled-cluster linear-response theory. This scheme is an extension of our earlier idea [N. J. Russ and T. D. Crawford, Chem. Phys. Lett., 2004, 400, 104] based on an atom-by-atom decomposition of the coupled-perturbed Hartree-Fock (CPHF) response of the component molecular orbitals to external electric and magnetic fields. We have applied this domain-selection scheme to a series of chiral molecules, including pseudo-linear structures (hydrogen molecule helices, fluoroalkanes, and [n]triangulanes), cage-like structures (beta-pinene, methylnorbornanone, and bisnoradamantan-2-one), and aromatic rings (1-phenylethanol). We find that the crossover points between the canonical- and local-correlation approaches are larger than for the conventional Boughton-Pulay domain scheme, in agreement with our earlier analysis of dipole-polarizabilities. Localization errors are reasonably small (a few percent) for pseudo-linear structures with domain sizes of approximately six to eight atoms. Cage-like molecules are significantly more problematic, requiring natural domain sizes of ten or more to obtain the most reliable localization errors.
Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, USA.
Nicholas J
NJ
Russ
T Daniel
TD
Crawford
D000218:Adamantane / Q000737:chemistry; D000465:Algorithms; D000081008:Bicyclic Monoterpenes; D001643:Bridged Bicyclo Compounds / Q000737:chemistry; D003198:Computer Simulation; D004574:Electromagnetic Fields; D005466:Fluorocarbons / Q000737:chemistry*; D006844:Hydrocarbons, Cyclic / Q000737:chemistry*; D008956:Models, Chemical; D039821:Monoterpenes / Q000737:chemistry; D009636:Norbornanes / Q000737:chemistry; D009904:Optical Rotation; D010626:Phenylethyl Alcohol / Q000737:chemistry; D011789:Quantum Theory
C497854:3-methylene-2-norbornanone; D000081008:Bicyclic Monoterpenes; D001643:Bridged Bicyclo Compounds; D005466:Fluorocarbons; D006844:Hydrocarbons, Cyclic; D039821:Monoterpenes; D009636:Norbornanes; C010789:beta-pinene; D010626:Phenylethyl Alcohol; D000218:Adamantane