Spectroscopic properties of trichlorofluoromethane CCl3F calculated by density functional theory

Density functional theory is used to generate local potential energy surfaces in normal coordinates for several chlorine isotopomers of trichlorofluoromethane (CCl3F, CFC11). An examination of predicted structures suggested that the PBE0 functional would be suitable. Anharmonic surfaces around the equilibrium geometries are reported, as determined by energies, gradients, and second derivatives. Vibrational levels for fundamentals, overtones and combination bands are reported, as well as harmonic frequencies, anharmonic constants, rotational constants, isotope shifts, and infrared intensities. These are compared with experimental information.