화학공학소재연구정보센터
Journal of Physical Chemistry A, Vol.103, No.7, 838-840, 1999
Jahn-Teller effect in VF3
A computational study of the two lowest-lying electronic states, (3)A(2') and E-3", of the VF3 molecule is reported. Highly sophisticated methods were used, including the coupled-cluster singles and doubles level augmented by a perturbative correction for connected triple excitations and the equation-of-motion coupled-cluster method in the singles and doubles approximation. In contrast to previous theoretical and experimental data, the present results predict the E-3" State to be the ground electronic state of VF3 in its trigonal planar D-3/1 conformation. The A(3)A(2') State is 1300 cm(-1) above the (XE)-E-3" state. The Jahn-Teller (JT) effect in the (XE)-E-3" state was studied. The three equivalent minima on the Jahn-Teller surface corresponding to the B-3(1) minimum are 270 cm(-1) below the D-3h energy and separated by only 24 cm(-1) barriers corresponding to (3)A(2) Saddle points. The JT distortions of the D-3h structure are appreciable; at the 3B1 minimum (C-2v symmetry), the molecule has one long V-F bond with R-1e (V-F-(1)) 1.768 Angstrom, two short bonds with R-2e (V-F-(2)) = R-3e (V-F-(3)) 1.748 Angstrom, and the bond angle alpha(e)(F-(2)-V-F-(3)) = 129 degrees. The available experimental data on the VF3 molecular structure and spectra (gas-phase electron diffraction and matrix IR and Raman spectroscopy) are discussed in light of the present results.