Toward the laboratory identification of cyclopropenylidene

Journal Article · Tue Jan 08 23:00:00 EST 1985 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00287a025· OSTI ID:5768286

Lee, T J; Bunge, A; Schaefer, III, H F

Nonempirical molecular electronic structure theory has been used to predict the geometries and energetics of the lowest singlet and triplet states of C-HC=CH. The closed-shell singlet ground state is predicted to lie about 70 kcal/mol below the lowest triplet state. Actually there are two low-lying triplet states, /sup 3/B/sub 1/ and /sup 3/A/sub 2/, which lie very close energetically. Ground-state cyclopropenylidene is predicted to have a dipole moment ..mu.. approx. 3.4 D, making it a very nucleophilic carbene. Vibrational frequencies are predicted for all three low-lying electronic states at the double-zeta plus polarization (DZ+P) self-consistent-field (SCF) or two-configuration (TC) SCF levels of theory. A comparison of the predicted harmonic frequencies of singlet cyclopropenylidene and cyclopropene at the SCF level of theory is made. These predictions should assist in the identification of cyclopropenylidene from matrix-isolation ir spectroscopy. 37 references, 3 figures, 8 tables.

• Research Organization: Lawrence Berkeley Lab., CA
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 5768286
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 107:1; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
ALKENES
CYCLOALKENES
DOCUMENT TYPES
ELECTRONIC STRUCTURE
ENERGY LEVELS
EXCITED STATES
EXTRAPOLATION
FORECASTING
HYDROCARBONS
INFRARED SPECTRA
MOLECULAR ORBITAL METHOD
NUMERICAL SOLUTION
ORGANIC COMPOUNDS
REVIEWS
SPECTRA
STABILITY
VIBRATIONAL STATES