Hyperfine splitting in N[sub 4][sup +] from ab Initio calculation

Journal Article · Thu May 12 04:00:00 EDT 1994 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100070a016· OSTI ID:7260594

Carmichael, I ^[1]

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1. Univ. of Notre Dame, IN (United States)

A quadratic configuration interaction calculation of the structure and magnetic hyperfine splitting constants in the tetranitrogen radical cation is reported. The species is determined to be linear, and splittings in close accord with experimental findings are calculated despite the large amounts of spin contamination in the unrestricted Hartree-Fock (UHF) reference wave function. Indeed, reasonable agreement is attained even with a modest double-[zeta] description of the single-particle space in the molecular orbital treatment, provided that the effect of amplitudes due to single replacements in the reference wave function is included in the cluster expansion. Improvements in the quality of the basis set lead to improved predictions of the unpaired spin density, indicating that such agreement is not fortuitous. An analysis is given of the contributions from various levels of excitation, up to quadruples, in the UHF determinant. Analogous results are also presented for various ionic states of atomic nitrogen and the dinitrogen radical cation. 51 refs., 1 fig., 8 tabs.

• OSTI ID: 7260594
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 98:19; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
99 GENERAL AND MISCELLANEOUS
990200* -- Mathematics & Computers
CALCULATION METHODS
CATIONS
CHARGED PARTICLES
COMPILED DATA
DATA
ELECTRONIC STRUCTURE
FUNCTIONS
HARTREE-FOCK METHOD
INFORMATION
IONS
MOLECULAR ORBITAL METHOD
NITROGEN IONS
NUMERICAL DATA
RADICALS
WAVE FUNCTIONS