Methylnitrene free radical. Ground state vibrational fundamentals and harmonic force field from jet‐cooled emission spectra of theà 3E–X̃ 3A2band system
| Autor: | P. C. Engelking, E. L. Chappell |
|---|---|
| Rok vydání: | 1988 |
| Předmět: | |
| Zdroj: | The Journal of Chemical Physics. 89:6007-6016 |
| ISSN: | 1089-7690 0021-9606 |
| DOI: | 10.1063/1.455415 |
| Popis: | The A 3E–X 3A2 UV emission spectra of the jet‐cooled methylnitrene radical CH3N and the isotopomers 13CH3N and CD3N have been examined with moderate resolution. Analysis of the vibrational band progressions gives a complete set of all six ground state vibrational fundamentals for CH3N: The symmetric hydrogen stretch, ν‘1=2943(04) cm−1; the symmetric hydrogen bend, ν‘2=1349(04) cm−1; the C–N stretch, ν‘3=1040(04) cm−1; the asymmetric hydrogen stretch, ν‘4=2989(04) cm−1; the scissors, ν‘5=1490(04) cm−1; and the rock, ν‘6=903(08) cm−1. A Jahn–Teller distortion in the 3E excited state activates ground state progressions of the e‐type modes. These vibrational frequencies, along with those from 13CH3N and CD3N, determine the 12 coefficients of a ground state harmonic force field. The resulting force constants indicate a strong C–N bond and weak C–H bonds, accompanying considerable departure from a usual methyl structure. The structure and force field are discussed in the context of a model involving sigma bon... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|