THE HYPERPOLARIZABILITY OF THE TRICYANOMETHANIDE MOLECULAR ION IN SOLUTION

Considering the tricyanomethanide ion [C(CN)(3)](-) as a prototype for octopole-like molecules we explore the solvent, correlation and frequ ency dependences of its polarizability and first hyperpolarizability u sing a reaction field response model with single- and multiconfigurati onal self-consistent wavefunctions. The convention problem of relating the hyperpolarizability obtained from the hyper-Rayleigh scattering t echnique and from computations is disentangled. The validity of the si mplifying two- and three-state models for the hyperpolarizability are examined.