Ab Initio Investigation of Spectroscopic Parameters for CrX63-: The Unexpected Role of Bond Length Variation - Size Really Matters
Résumé
Ligand field states were calculated in the CrX63- series with X = F, Cl, Br, and I from first principles, and the ligand field parameter, Δ, was deduced. The decrease in Δ follows the spectrochemical series; π effects are usually invoked to justify this trend. It is shown that while the covalence increases, the π effect decreases and that the key role in the decrease in Δ is played by the increase in bond length in the halide series.