Theoretical study of structures and energies of acetylene, ethylene, and vinyl radical and cation

Journal Article · Tue Jun 14 20:00:00 EDT 1988 · J. Chem. Phys.; (United States)

DOI:https://doi.org/10.1063/1.454303· OSTI ID:5307185

Curtiss, L A; Pople, J A

A systematic study of the structures and energies of acetylene, ethylene, and vinyl radical and cation using high levels of ab initio molecular orbital theory, including correlation effects beyond fourth order perturbation theory, is presented. In agreement with previous theoretical studies, the present theory predicts that the bridged form of C/sub 2/H/sup +//sub 3/ is more stable than the classical form with an energy difference of 3.1 kcal/mol (including zero point energies). The bond dissociation energy of C/sub 2/H/sub 4/,D/sub 0/(C--H), is calculated to be 110.2 kcal/mol in agreement with the recent photoionization study of Berkowitz et al. and in significant disagreement with several previous experimental studies. Finally, triplet vinyl cation is studied for the first time and is calculated to be 54.5 kcal/mol higher in energy than the singlet ground state.

• Research Organization: Argonne National Laboratory, Chemical Technology Division/Materials Science Program, Argonne, Illinois 60439-4837
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5307185
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 88:12; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ACETYLENE
AFFINITY
ALKENES
ALKYL RADICALS
ALKYNES
CATIONS
CHARGED PARTICLES
CORRELATIONS
DISSOCIATION ENERGY
ELECTRON CORRELATION
ENERGY
ETHYLENE
HYDROCARBONS
IONIZATION POTENTIAL
IONS
MOLECULAR IONS
MOLECULAR STRUCTURE
ORGANIC COMPOUNDS
RADICALS
STEREOCHEMISTRY
VINYL RADICALS