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

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.