Adequate representation of charge polarization effects leads to a successful treatment of the CF4 + SiCl4 → CCl4 + SiF4 reaction by density functional theory

Abstract

Adequate polarization functions reduce the error of density functional theory (DFT) for the heat of reaction for CF₄ + SiCl₄ from ∼9–12 kcal mol⁻¹ to ∼2–4 kcal mol⁻¹, and using an improved density functional further reduces it to ∼1 kcal mol⁻¹. This reaction was previously identified as a stumbling block for DFT, but we show that the problem with the previous calculations was not DFT but rather inadequate basis sets to account for intramolecular charge polarization.