Theoretical study of pKa for perchloric acid

The pKa value of perchloric acid was successfully calculated with high accuracy by using high-level ab initio methods, including G2 and CBS-QB3, DFT-based method, complete basis sets (CBS), and Gaussian-n methods. Solvation energies were calculated using the CPCM and IEF-PCM continuum models at the HF and B3LYP levels. Excellent agreement (to within 0.2 pKa units) was obtained between the calculated and experimentally determined values.