On the heat of formation of NH

Abstract

Experiments giving information on the heat of formation of NH have been reanalyzed. It has been found that studies on the dissociative excitation or ionizaton of NH-containing species give upper limits to ΔH°f0(NH) substantially lower than the JANAF value of 3.90 eV. The most reliable of these experiments give an upper limit of 3.63±0.10 eV in agreement with recent spectroscopic studies. The experiments given most weight in the JANAF compilation have been reviewed. All have been found to be more compatible with a lower heat of formation of NH than 3.9 eV. It is recommended that a new value of 3.65±0.10 eV be adopted for ΔH°f0(NH).