The semirigid bender model of Bunker and Landsberg [J. Mol. Spectrosc. 67, 374-385 (1977)] has been used to determine effective bending potentials for C3 in many of the lower stretching vibrational states from recently published experimental measurements on the ground state of this molecule. No barrier to linearity is found in the effective bending potential for either the zero point (v1 = v3 = 0) or the equilibrium stretching states, however, the effective potentials show a very flat minimum in both cases. The effective bending potential develops a much sharper minimum as the symmetric stretch (ν1) is excited. By contrast, it develops a barrier at the linear configuration as the antisymmetric stretching vibration (ν3) is excited. These observations are qualitatively rationalized by considering the bending angle dependence of the G-matrix elements for the stretching vibrations.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Physical and Theoretical Chemistry