文摘
Refractive indices of metal- and metalloid-containing compounds are systematically evaluated using the Lorentz–Lorenz equation with polarizabilities obtained via density functional theory (DFT). Among exchange-correlation functionals studied, the long-range corrected (LC) fuctionals yield the lowest errors for the polarizabilities of gaseous compounds and refractive indices of liquids. The LC-DFT predicts very well the wavelength dependence of refractive indices. A scheme for computing Abbe numbers of organometallic and organometaloid compounds is proposed and a refractive index – Abbe number plot for 80 compounds is constructed. The compounds containing heavier metals tend to have higher refractive index and lower Abbe number, but several outliers, among them Te(CH3)2, Ni(PF3)4, Sb(C2F3)3, Hg(C2F3)2, are found. For Hg(C2F3)2, also the effect of intramolecular and intermolecular degrees of freedom on polarizability is investigated. The absolute relative error in polarizability decreases from 5.7% for monomer model to 1.7% when a dimer model (derived from the available experimental crystal data) is employed.