Electric dipole moments of HF–C2H2, HF–C2H4, and HF–C3H6

Electric dipole moments of HF–cyclopropane, HF–ethylene, and HF–acetylene have been determined using the molecular beam electric resonance technique. The dipole moments of HF–C3H6, HF–C2H4, and HF–C2H2 are 2.5084(28), 2.3839(45), and 2.3681(28) D, respectively. The induced dipole moments of these systems are discussed, along with that of HF–benzene which has been previously determined. The induced dipole moments do not scale simply with hydrocarbon polarizabilities. Moreover, they do not correlate well with the frequency shifts of the HF submolecule stretching vibration measured in matrix isolation studies.