The proton-bound complex Cl−⋯H-CCl3: A high-level theoretical study

Large-scale coupled cluster calculations within variant CCSD(T) have been employed to study major portions of the potential energy and electric dipole moment surfaces for the hydrogen-bonded anionic complex Cl−⋯H-CCl3. The recommended dissociation energy D0 is 6280 cm−1 or 75.1 kJ mol−1, with an estimated error of ca. 1%. Upon complex formation, the weak CH stretching vibration (ν1) of free HCCl3 experiences an intensity enhancement by four orders of magnitude, with anharmonicity effects playing an important role. The band origins of the ν1 bands of 35Cl−⋯H-C35Cl3 and 35Cl−⋯H-D35Cl3 are calculated at 2553 and 1949 cm−1, respectively.