Potential energy surface tunneling splitting

With one exception, these results are based solely on quantum-chemical calculations of the potential energy surface. Theoretical evaluation of the transfer dynamics has been attempted only for the formic acid dimer, for which two general level splittings have been observed and assigned to synchronous double proton tunneling in the ground state and a vibrational excited state, respectively. 

Calculations of Rotational Tunneling Splittings. The calculation of tunnel splittings and the comparison with experiment offer a severe test of the knowledge of the potential energy surface. As all measurements are made at... 

There have been four more complete attempts to calculate the tunneling splittings, in which multidimensional potential energy surfaces were used. Three of the calculations, by Barton and Howard, by Hancock, the author, and coworkers,203 and by Bunker et... 

In Table 4.6, the long progression of the 26 mode has been observed and the corresponding tunneling splitting decreases monotonically with its excitation. To know the symmetry of the potential energy surface, we need information on the normal mode. It has been repeatedly pointed out [75,76] that the strong Duschinsky effect between the V25 mode and the V26 mode is found in the X - A electronic... 

As was mentioned before, the present analysis is based on the assumption that the symmetry of the potential energy surface of A state is similar to that of the ground state X and that the stable structure of the excited state is planar. There have been carried out some quantum chemical calculations of the excited A state [81,84-87]. However, the planarity of the equilibrium geometry of this state is not satisfactorily clarified yet [81,86,87]. Wojcik et al. [87] have obtained slightly nonplanar structure, but their analysis of tunneling splitting is in good accordance with the analysis mentioned above. 

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