MCSCF potential energy surface for the high barrier adiabatic 1 /sup 4/. sigma. /sup -/ pathway of the O/sup +/(/sup 4/S)+N/sub 2/(X /sup 1/. sigma. /sub g//sup +/). -->. NO/sup +/(X /sup 1/. sigma. /sup +/) +N(/sup 4/S) reaction

Journal Article · Sat Mar 15 00:00:00 EST 1980 · J. Chem. Phys.; (United States)

OSTI ID:5542082

Hopper, D G

The collinear /sup 4/..sigma../sup -/ pathway for the state-specific O/sup +/(/sup 4/S)+N/sub 2/(X /sup 1/..sigma../sub g//sup +/) ..-->..NO/sup +/(X /sup 1/..sigma../sup +/)+N(/sup 4/S) reaction has been surveyed with ab initio calculations. A ninety-nine configuration, fifteen orbital multiconfiguration self-consistent field (MCSCF) wave function, involving the use of a double-zeta plus polarization one-electron basis, was developed for the long range /sup 4/..sigma../sup -/ state. This long range /sup 4/..sigma../sup -/ state has the character of O/sup +/+N/sub 2/ for long R/sub NO/, or of N+NO/sup +/ for long R/sub NN/, and is for most geometries, the lowest, or 1 /sup 4/..sigma../sup -/, state. The ab initio exothermicity computed with the present wave function is 0.93 eV, compared to an accurate experimental value of 1.10 eV. The saddle-point in the energy surface is 8.0 eV above O/sup +/+N/sub 2/, with critical values of R*/sub NN/=1.48 +- 0.02 A and R*/sub NO/ =1.38 +- 0.02 A. These values are 0.38 and 0.32 A greater than the equilibrium bond lengths of N/sub 2/(X /sup 1/..sigma../sub g//sup +/) and NO/sup +/(X /sup 1/..sigma../sup +/). The present wave function reproduces the experimental bond lengths of these two diatomics to within 0.01 A when the third atom is removed to 500 a.u. (264.6 A). Preceding the barrier on the O/sup +/+N/sub 2/ side is an appreciable polarization well. With the present wave function the attributes of this well are D/sup 0/ (N/sub 2/--O/sup +/) =0.38 eV, R/sub NN//sup E/=1.108 A, R/sub NO//sup e/ =2.350 A, theta/sup e//sub NNO/=180/sup 0/, k/sup e//sub NN/=24.679 md/A, k/sup e//sub NO/=0.295 md/A, k/sub theta/=0.0366 md/A. There is also a smaller polarization well on the N+NO/sup +/ side. Although the ion--atom interaction is more stable at C/sub s/ the latter well is bound by 0.02 eV at 180/sup 0/ with R/sup e//sub NN/=3.34 A, and R/sup e//sub NO/=1.07 A.

• Research Organization: Theoretical Chemistry Group, JAYCOR, Dayton, Ohio 45431
• OSTI ID: 5542082
• Journal Information: J. Chem. Phys.; (United States), Vol. 72:6
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
IONOSPHERE
CHEMICAL REACTIONS
NITROGEN
OXYGEN IONS
ATOMIC IONS
NITRIC OXIDE
POTENTIAL ENERGY
CHALCOGENIDES
CHARGED PARTICLES
CRYOGENIC FLUIDS
EARTH ATMOSPHERE
ELEMENTS
ENERGY
FLUIDS
IONS
NITROGEN COMPOUNDS
NITROGEN OXIDES
NONMETALS
OXIDES
OXYGEN COMPOUNDS
PLANETARY IONOSPHERES
400201* - Chemical & Physicochemical Properties