Bonding and ionization energies of N–F and P–F compounds

Abstract

NF3, N2F4, NF2, PF3, P2F4, PF2, and PF2I have been studied by photoionization mass spectrometry. Modified or confirmatory values have been obtained for the heats of formation of NF+3, NF+2, and NF+ and the ionization potentials of NF3 and NF2. The stepwise bond energies are deduced to be D00(NF) =3.27±0.02 eV; D00(FN–F) =2.85±0.02 eV; and D00(F2N–F) =2.47±0.01 eV. Heats of formation at 0 K have been measured for PF+2 (89.6±0.5 kcal/mol), PF+ (≤214.8 kcal/mol), and PF2I (−142.3±1.0 kcal/mol). The directly measured ionization potential of PF2 is 8.85±0.01 eV. The stepwise bond energies are found to be D00(PF)