INTERNAL-ROTATION OF MOLECULES WITH 2 INEQUIVALENT METHYL-GROUPS - MICROWAVE-SPECTRA OF ISOTOPICALLY SUBSTITUTED TRANS-N-METHYLETHYLIDENIMINES

被引:14
作者
BOSSERT, W
BAUDER, A
GUNTHARD, HH
机构
[1] Laboratory for Physical Chemistry, Swiss Federal Institute of Technology
关键词
D O I
10.1016/0301-0104(79)80156-1
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
Four isotopic species of trans-N-methylethylidenimine (CH3CHNCH3, CH3CDNCH3, CH3CHNCD3 and CD3CDNCH3) have been investigated. The microwave spectra of the last two species have been measured and assigned in the frequency range from 8 to 40 GHz for the first time. A rigorous analysis of the internal rotation splittings for these molecules with two inequivalent methyl groups is presented. Accurate calculations of transition frequencies and line strengths have been performed by diagonalizing the energy matrices in a stepwise procedure. Molecular constants for overall and internal rotations have been adjusted from the observed transition frequencies of each isotopic species. The internal rotation barriers have been found to be independent of the isotopic composition. A value of 540(2) cm-1 was obtained for the CCH3 top and a value of 698(9) cm-1 for the NCH3 top. © 1979.
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页码:367 / 393
页数:27
相关论文
共 33 条
[1]   PYROLYTIC PRODUCTION AND MICROWAVE-SPECTRA OF LIGHT AND HEAVY N-METHYLMETHYLENIMINE [J].
BAK, B ;
LARSEN, NW ;
SVANHOLT, H .
ACTA CHEMICA SCANDINAVICA SERIES A-PHYSICAL AND INORGANIC CHEMISTRY, 1977, 31 (09) :755-758
[2]   INTERNAL-ROTATION IN ACETALDEHYDE [J].
BAUDER, A ;
GUNTHARD, HH .
JOURNAL OF MOLECULAR SPECTROSCOPY, 1976, 60 (1-3) :290-311
[3]  
BAUDER A, 1976, MOL PHYS, V31, P647
[4]   ISOMETRIC GROUP OF NON-RIGID MOLECULES - NEW APPROACH TO SYMMETRY GROUPS OF NON-RIGID MOLECULES [J].
BAUDER, A ;
MEYER, R ;
GUNTHARD, HH .
MOLECULAR PHYSICS, 1974, 28 (05) :1305-1343
[6]   STARK EFFECT AND ISOMETRIC GROUPS ON NONRIGID MOLECULES .1. GENERAL THEORY AND DETERMINATION OF RELATIVE SIGNS OF COMPONENTS OF ELECTRIC-DIPOLE MOMENT OF SEMIRIGID MOLECULES WITH ONE AND 2 SYMMETRIC ROTORS [J].
BOSSERT, W ;
EKKERS, J ;
BAUDER, A ;
GUNTHARD, HH .
CHEMICAL PHYSICS, 1978, 27 (03) :433-463
[7]  
BOSSERT W, 1978, THESIS ETH ZURICH
[8]  
CRAWFORD BL, 1940, J CHEM PHYS, V8, P273
[9]  
DREIZLER H, 1961, Z NATURFORSCH PT A, V16, P1354
[10]  
DREIZLER H, 1962, Z NATURFORSCH PT A, VA 17, P712