Quantum-mechanical model relating negative-ion polarizabilities in free space and in an ionic crystal Original Research Article

Earlier Wilson and Curtis used a classical model of a compressible conducting sphere to relate the free-negative-ion polarizability α−o to that α− of the negative ion in a crystal field, such as in an alkali-halide lattice. Here the adjustable parameter in the Wilson–Curtis model is interpreted in terms of quantum-mechanical expectation values of a single anion in free space together with a factor containing fingerprints of the crystal structure (e.g. NaCl or CsCl). The quantum-mechanical valence-electron rescaling framework should then also be useful for other purposes, e.g. to treat dynamic polarizabilities in a comparatively simple manner.