Molecular structures of methyldifluoroarsine, CH3AsF2, and dimethylfluoroarsine, (CH3)2AsF, in the gas phase as determined by electron diffraction and ab initio calculations

The molecular structures of gaseous CH3AsF2 and (CH3)2AsF were determined by electron-diffraction experiments and ab initio computations. Findings indicated that both As-C and As-F bond lengths are shortened by increasing numbers of fluorine atoms but that the angles CAsF and FAsF are almost invariant in the series (CH3)3As, (CH3)2AsF, CH3AsF2, and AsF3.