Vibronic coupling pseudo

VIBRONIC COUPLING IN INORGANIC SYSTEMS PHOTOCHEMISTRY, CONICAL INTERSECTIONS, AND THE JAHN-TELLER AND PSEUDO-JAHN-TELLER EFFECTS... 

Figure 69 Vibronic coupling for octahedral copper(II) (a) dynamic Jahn-Teller effect (alg and blg) (b) pseudo...

A parameterization method of the Hamiltonian for two electronic states which couple via nuclear distortions (vibronic coupling), based on density functional theory (DFT) and Slaters transition state method, is presented and applied to the pseudo-Jahn-Teller coupling problem in molecules with an s2-lone pair. The diagonal and off-diagonal energies of the 2X2 Hamiltonian matrix have been calculated as a function of the symmetry breaking angular distortion modes and r (Td)] of molecules with the coordination number CN = 3... 

Vibronic Coupling in Inorganic Systems Photochemistry, Conical Intersections, and the Jahn-Teller and Pseudo-Jahn-Teller Effects Russell G. Mckinlay, Justyna M. Zurek and Martin J. Paterson... 

Case of V > A vibronic ( i + P) (g) e -problem. Providing t > 0 (ground state E) and strong transfer, the lower sheet of the adiabatic surface represents the so-called Mexican hat characteristic of the E e-JT problem [46,47]. In this case the electronic distribution is dynamically averaged, and the system behaves as fully delocalized. The decrease of the electron transfer and/or the increase of the vibronic coupling results in the appearance of three minima (pseudo-JTE),... 

Piepho has treated intervalence transitions using a relatively simple three-center molecular orbital model in which vibronic coupling is introduced as a pseudo-Jahn-Teller perturbation. This could be a valuable approach, and it can probably be generalized to a great variety of problems. In this report, Piepho uses the approach to calculate intervalence transition band shapes for a range of vibronic couplings, and she discusses the vibronic criteria for valence trapped and delocalized systems. 

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