Photoelectron spectroscopy of CH sub 2 N sup minus

Journal Article · Thu Feb 28 23:00:00 EST 1991 · Journal of Chemical Physics; (USA)

DOI:https://doi.org/10.1063/1.459773· OSTI ID:6190062

Cowles, D C; Travers, M J; Frueh, J L; Ellison, G B ^[1]

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1. Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado (US)

We have measured the negative ion photoelectron spectra of CH{sub 2}N{sup {minus}} and CD{sub 2}N{sup {minus}} and find the electron affinities: EA(CH{sub 2}N)=0.511{plus minus}0.008 eV and EA(CD{sub 2}N)=0.498{plus minus}0.011 eV. Franck--Condon simulations of these spectra are carried out and we estimate the CH{sub 2}N{sup {minus}} and CH{sub 2}N geometry differences; we fit our spectra with the following (constrained) molecular structures. We combine our EA(CH{sub 2}N) with the results of previous gas phase ion studies to extract a number of thermochemical parameters (kcal/mol): {ital D}{sup {ital o}}{sub 0}(CH{sub 2}N--H)=85{plus minus}5, {ital D}{sup {ital o}}{sub 0}(H--HCN)=23{plus minus}6, {ital D}{sup {ital o}}{sub 0}(H{sub 2}C--N)=144{plus minus}6, and the isomerization enthalpy of H{sub 2}CN{sup +}{r arrow}HCNH{sup +} is {Delta}{ital H}{sub isom}({ital C}{sub 2{ital v}}{r arrow}{ital C}{sub {infinity}{ital v}})={minus}51{plus minus}7. Attempts to calculate the geometry and vibrational frequencies of the H{sub 2}CN radical are disappointing. Unrestricted Hartree--Fock and second-order Moller--Plesset {ital ab} {ital initio} calculations in a 6-31++G** basis produce badly spin-contaminated wave functions which do not reproduce the experimental findings.

• DOE Contract Number: FG02-87ER13695
• OSTI ID: 6190062
• Journal Information: Journal of Chemical Physics; (USA), Journal Name: Journal of Chemical Physics; (USA) Vol. 94:5; ISSN JCPSA; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
AFFINITY
ANIONS
CHARGED PARTICLES
DISSOCIATION HEAT
ELECTRON SPECTROSCOPY
ELECTRONEGATIVITY
ENTHALPY
IONS
MOLECULAR IONS
MOLECULAR STRUCTURE
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHOTOELECTRON SPECTROSCOPY
PHYSICAL PROPERTIES
REACTION HEAT
SPECTROSCOPY
THERMODYNAMIC PROPERTIES