C2H radical: 13C hyperfine interaction and optical spectrum
- 15 May 1974
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 60 (10) , 3817-3823
- https://doi.org/10.1063/1.1680824
Abstract
C2H was prepared by photolysis of acetylene, 90% 13C‐substituted acetylene, or iodoacetylene and trapped in solid argon at 4°K. A complete analysis of all hyperfine‐interaction and g tensor components was made for the randomly oriented 2Σ molecules yielding the following parameters (in solid argon): g∥=g⊥=2.0025(5), A⊥(H)=41(1), A∥(H)=51(1), A⊥(13Cα)=863(1), A∥(13Cα) =980(1), A⊥(13Cβ)=139(1), A∥(13Cβ) =191(1) MHz. Approximate spin densities are compared with an extended basis INDO calculation of Morikawa and Kikuchi. Weak optical absorption spectra were observed at about 10 000 and 3300 Å. The former is assigned to an A2∏i←X2Σ transition with (0,0,0) at 10 080 Å (in solid argon) where the upper state C–C stretching frequency ν′3 =1560 cm−1. The assignment of the 3300 Å system (s) is less definite, but it may involve a B2A′←X2Σ, bent ← linear transition since the observed bands cannot definitely be assigned to an expected B2Σ←X2Σ transition.Keywords
This publication has 18 references indexed in Scilit:
- An SCF-MO-INDO Study of Isotropic and Anisotropic Hyperfine Coupling Constants for Sigma RadicalsBulletin of the Chemical Society of Japan, 1972
- Laser Excited Fluorescence Studies of Matrix Isolated C2−The Journal of Chemical Physics, 1972
- Vibrational spectra and assignment of iodoacetyleneJournal of the Chemical Society, Faraday Transactions 2: Molecular and Chemical Physics, 1972
- C2 and C2− Spectra Produced by the X Irradiation of Acetylene in Rare-Gas MatricesThe Journal of Chemical Physics, 1971
- A new spectrum associated with diatomic carbonCanadian Journal of Physics, 1968
- Molecular Dissociative Equilibria in Carbon StarsThe Astrophysical Journal, 1967
- Radiation Damage in Organic Crystals. I. CH(COOH)2 in Malonic Acid1Journal of the American Chemical Society, 1960
- Electron Spin Resonance of an Irradiated Single Crystal of Alanine: Second-Order Effects in Free Radical ResonancesThe Journal of Chemical Physics, 1960
- ULTRAVIOLET ABSORPTION SPECTRA OF HCN AND DCN: I. THE α—X AND β—X SYSTEMSCanadian Journal of Physics, 1957
- 468. The electronic orbitals, shapes, and spectra of polyatomic molecules. Part III. HAB and HAAH moleculesJournal of the Chemical Society, 1953