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Complete Structure of Gauche 1,1,2,2-Tetrafluoroethane Determined by Microwave Spectroscopy



B Mate, Angela R. Hight Walker, R D. Suenram, N Craig


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.
Journal of Physical Chemistry A
No. 42


1, 1, 2, 2-tetrafluoroethane, electric dipole moment, F134, fourier transform microwave spectrum, microwave


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 June 24, 2024)


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Created October 1, 2000, Updated February 17, 2017