Gaseous H2N03+ ions have been obtained from direct protonation of nitric acid by H3+, CH5+, and H30+ as well as from the protonation of C2HSON02fo llowed by CzH4 loss. The proton affinity of nitric acid has been estimated to be 168 f 3 kcal mol-' from the results of bracketing experiments carried out by FT-ICR and CI mass spectrometry. Structural analysis by MIKE and CID spectrometry of H2N03+ ions and of their 180-labeled isotopomers obtained from the exchange with HZ1"0 provides strong evidence for the existence of two isomers, characterized by the (HO)zNO+ and the Hz0.NO2+ structure, and for the higher stability of the latter. The results are consistent with those of independent MO SCF calculations, pointing to the higher stability of the H20.N02+ structure.
Protonated nitric acid. Structure and relative stability of isomeric H2N03+ ions in the gas phase / Cacace, Fulvio; M., Attinà; DE PETRIS, Giulia; Speranza, Maurizio. - In: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY. - ISSN 0002-7863. - STAMPA. - 112:3(1990), pp. 1014-1018. [10.1021/ja00159a018]
Protonated nitric acid. Structure and relative stability of isomeric H2N03+ ions in the gas phase
CACACE, Fulvio;DE PETRIS, GIULIA;SPERANZA, Maurizio
1990
Abstract
Gaseous H2N03+ ions have been obtained from direct protonation of nitric acid by H3+, CH5+, and H30+ as well as from the protonation of C2HSON02fo llowed by CzH4 loss. The proton affinity of nitric acid has been estimated to be 168 f 3 kcal mol-' from the results of bracketing experiments carried out by FT-ICR and CI mass spectrometry. Structural analysis by MIKE and CID spectrometry of H2N03+ ions and of their 180-labeled isotopomers obtained from the exchange with HZ1"0 provides strong evidence for the existence of two isomers, characterized by the (HO)zNO+ and the Hz0.NO2+ structure, and for the higher stability of the latter. The results are consistent with those of independent MO SCF calculations, pointing to the higher stability of the H20.N02+ structure.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
