Nuclear Magnetic Resonance : Structure of the Amino Group. II

Abstract

The nuclear magnetic resonance spectra of powder samples of hydroxylamine hydrochloride and oxamide have been obtained. N–H bond distances were calculated to be 1.036±0.025 A in formamide, and 1.039±0.013 A in oxamide, assuming a 120° bond angle and a planar structure in each case. An attempt is made to correlate the N–H bond lengths with the hydrogen bond length by a modification of Lippincott's theory of the linear O≡O hydrogen bond. The rigid lattice second moment of cyanamide was also measured. The result is not consistent with the assumption of an ammonia‐like N–H bond structure, but requires a larger H–H separation.