The microwave spectrum, harmonic force field, and structure of difluorodichloromethane

Very large numbers of rotational transitions have been accurately measured for ¹²CF ₂³⁵Cl ₂, ¹²CF ₂³⁵Cl ³⁷Cl, and ¹³CF ₂³⁵Cl ₂, and have been analyzed for rotational constants and quartic centrifugal distortion constants. The distortion constants have been combined with vibrational wavenumbers (both from the literature and from the present work), and with ab initio force constants also evaluated in the present work, to give an approximate harmonic force field. The rotational constants and force field have been used to evaluate ground state effective, substitution, and ground state average structures for the molecule.