Photoionization mass spectrometric study of N sub 2 H sub 2 and N sub 2 H sub 3 : N--H, N=N bond energies and proton affinity of N sub 2

Journal Article · Sun Sep 15 00:00:00 EDT 1991 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.461761· OSTI ID:5312787

Ruscic, B; Berkowitz, J ^[1]

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1. Chemistry Division, Argonne National Laboratory, Argonne, Illinois (USA)

The photoion yield curves of N{sub 2}H{sup +}{sub 2}, N{sub 2}H{sup +}, and H{sup +}{sub 2} from N{sub 2}H{sub 2} have been studied by photoionization mass spectrometry. The adiabatic ionization potential of N{sub 2}H{sub 2} determined (9.589 {plus minus} 0.007 eV) is in excellent agreement with that obtained by photoelectron spectroscopy (PES). The appearance potential of N{sub 2}H{sup +} (10.954 {plus minus} 0.019 eV at 0 K) is in good agreement with earlier electron impact measurements. The appearance potential of H{sup +}{sub 2} ({lt}13.52{sub 6} {plus minus}0.03; probably {le}13.403 {plus minus}0.036 eV, at 0 K) leads to {Delta}{ital H}{sup 0}{sub {ital f}{sub 0}} (N{sub 2}H{sub 2}) {gt}43.8 {plus minus}0.7; probably {ge}46.6 {plus minus}0.8 kcal/mol. Consequently, proton affinity (PA) (N{sub 2}) {lt}121.8 {plus minus}0.8; probably {le}119.0 {plus minus}0.9 kcal/mol, which is in good agreement with results from proton transfer experiments and with most {ital ab} {ital initio} calculations. The N double bond'' energy determined from N{sub 2}H{sub 2}{r arrow}2NH is {lt}126.6 {plus minus}1.0; probably {le}123.8 {plus minus}1.1 kcal/mol. The adiabatic ionization potential of N{sub 2}H{sub 3} is found to be 7.61{plus minus}0.01 eV. This observation leads to {ital D}{sub 0} (H{sub 2}NNH--H)=80.8{plus minus}0.3 kcal/mol, and {ital D}{sub 0}(HNNH--H){congruent}43.8{plus minus}1.1 kcal/mol.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5312787
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 95:6; ISSN JCPSA; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
CATIONS
CHARGED PARTICLES
CHEMICAL BONDS
ENTHALPY
FORMATION HEAT
HYDRIDES
HYDROGEN COMPOUNDS
IONIZATION
IONIZATION POTENTIAL
IONS
MASS SPECTROSCOPY
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
PHOTOIONIZATION
PHYSICAL PROPERTIES
REACTION HEAT
SPECTROSCOPY
THERMODYNAMIC PROPERTIES