Page 276 - Strategies and Applications in Quantum Chemistry From Molecular Astrophysics to Molecular Engineer

VIBRATIONAL MODULATION EFFECTS ON EPR SPECTRA 259
In the above equation, h is the Planck constant, and c the speed of light. The mean values
at the absolute temperature T are obtained from the same equations by the of (j + 1/2) by

where K is the Boltzmann constant.From one side, Eq. (Al) shows that < s > and the cubic
force constants have opposite signs. On the other side, Figure 4 shows that in the

case of and have the same sign near the equilibrium structure. As a
result, the linear term in Eq. (8) is negative, thus counterbalancing the positive quadratic
term.

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