Reaction paths for the dissociation a-italic-tilde /sup 3/A'' CH/sub 2/CO. -->. X /sup 3/B/sub 1/ CH/sub 2/ + X /sup 1/. sigma. /sup +/ CO

Journal Article · Fri Jul 01 00:00:00 EDT 1988 · J. Chem. Phys.; (United States)

OSTI ID:7148237

Allen, W D; Schaefer, III, H F

An ab initio investigation of the (C/sup II//sub s/) in-plane bent /sup 3/A'' CH/sub 2/CO..-->..X /sup 3/B/sub 1/ CH/sub 2/+X /sup 1/summation/sup +/CO and the (C/sup I//sub s/) out-of-plane bent /sup 3/A' CH/sub 2/CO..-->..X /sup 3/B/sub 1/ CH/sub 2/+X /sup 1/summation/sup +/CO dissociation paths has been performed. Geometrical structures, vibrational frequencies, and quadratic force constants have been determined at the DZP SCF and DZP CISD levels of theory for the X /sup 1/A/sub 1/, /sup 3/A'', and /sup 3/A' states of ketene and for the /sup 3/A'' and /sup 3/A' transition states for dissociation. The DZP CISD structure for A-italic-tilde /sup 1/A'' ketene is also reported. Final energetic predictions for triplet ketene dissociation have been obtained from large-basis (QZ2P and QZ2P+f) UMP4(SDTQ) calculations at the DZP CISD geometries. The C/sup II//sub s/ stationary point for /sup 3/A'' ketene dissociation is a true transition state with r(C--C) = 2.071 A at the DZP CISD level of theory. The corresponding C/sup I//sub s/ stationary point for /sup 3/A' ketene is actually a super transition state for the interconversion of two equivalent /sup 3/A''C/sup II//sub s/ transition states for dissociation.

• Research Organization: Combustion Research Facility, Sandia National Laboratories, Livermore, California 94550, and Department of Chemistry and Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720
• OSTI ID: 7148237
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 89:1; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DISSOCIATION
ELECTRONIC STRUCTURE
ENERGY LEVELS
EXCITED STATES
GEOMETRY
KETENES
KINETICS
MATHEMATICS
MOLECULAR STRUCTURE
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
REACTION KINETICS
VIBRATIONAL STATES