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Complete Structure of Gauche 1,1,2,2-Tetrafluoroethane Determined by Microwave Spectroscopy
Published
Author(s)
B Mate, Angela R. Hight Walker, R D. Suenram, N Craig
Abstract
The complete molecular structure of the high-energy, gauche rotamer of 1,1,2,2-tetrafluoroethane (TFEA), Freon F134, has been determined using Fourier transform microwave spectroscopy. A total of five different 13C and 2H substituted isotopomers, in addition to the normal species were studied. Unlike the nonpolar anti rotamer, the gauche form has a permanent electric dipole moment, which permits a direct rotational analysis. The electric dipole moment was also determined using the Stark-effect of two low-J transitions. The resulting dipole moment is c = 8.186(7) x 10-30 C m [2.454(2) Debye]. The experimental results for the geometric parameters of TFEA are compared with two recent ab initio calculations.
Mate, B.
, Hight, A.
, Suenram, R.
and Craig, N.
(2000),
Complete Structure of Gauche 1,1,2,2-Tetrafluoroethane Determined by Microwave Spectroscopy, Journal of Physical Chemistry A
(Accessed October 21, 2025)