Refractive indices of organo-metallic and -metalloid compounds: A long-range corrected DFT study.

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(C2 F3 )3 , Hg(C2 F3 )2 , are found. For Hg(C2 F3 )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. © 2016 Wiley Periodicals, Inc.