MASS SPECTROMETRIC MEASUREMENT OF 15N ENRICHMENT IN NITROGEN OBTAINED BY DUMAS COMBUSTION

A rapid accurate Dumas method for determining 15N enrichments of from 0.37 to 100% is described. Whereas compounds with only one nitrogen atom exhibit random pairing in the nitrogen molecule formed during combustion, equilibration is incomplete in compounds with two or more variously bonded (NN, ON, and CN) nitrogen atoms. Failure to equilibrate is presumed to result from differences in bond energy between nitrogen and adjacent atoms. It is an advantage in revealing unequal enrichments of the nitrogen atoms present and in detecting nitrogenous impurities. © 1969.