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The evolution in the static longitudinal polarizability and second hyperpolarizability of the C 4 H 2 through C 54 H 2 oligomers of polyyne is studied at the Hartree-Fock level of theory. We find that the calculated values are highly sensitive to the adopted geometry. Using improved geometries, new extrapolation procedures and careful finite field determinations we extend earlier work by others so as to provide reliable estimates for the above properties in the infinite polymer limit.

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The static polarizability and first hyperpolarizability of the water trimer anion: Ab initio study Ab initio study of the dipole polarizability and the first hyperpolarizability of heterocyclics AIP Conf. Proc. 330, 74 (1995); 10.1063/1.47853 Ab initio studies of the polarizabilities of retinal analogsThe longitudinal polarizability, ␣ zz , and second order hyperpolarizability, ␥ zzzz , of the (C 4 H 3 N͒ R H 2 oligopyrroles, where Rϭ1Ϫ9, are determined at the Hartree-Fock ͑HF͒ level of theory using a 6-31G basis set. The effect of electron correlation is taken into account using Moller-Plesset perturbation theory through second order for the Rϭ1Ϫ5 oligopyrroles. Methods for extrapolation to the infinite polymer values are explored. The convergence behavior of the correlated results as a ratio with the corresponding HF values may indicate that a scaled HF procedure could be appropriate for finding correlated estimates to the infinite polymer property values. We also propose a generalized finite field recipe which can easily be used in conjunction with popular black-box electronic structure programs for determining molecular polarizabilities through second order. The ␣ zz and ␥ zzzz values obtained from using this procedure on a variety of polyacetylene and polypyrrole oligomers are in excellent agreement with those derived through analytical procedures.