Recently we discussed the Renner-Teller effect in triatomic molecules [J. Chem. Phys. 125, 094102 (2006)]. In that article the main message is that the Renner-Teller phenomenon, just like the Jahn-Teller phenomenon, is a topological effect. Now we extend this study to a tetra-atomic system, namely, the C(2)H(2) (+) ion, for which topological effects are revealed when one atom surrounds the tria...

For a rigorous quantum simulation of nonadiabatic dynamics of electrons and nuclei, knowledge of not only the first-order but also the second-order nonadiabatic couplings (NACs) is required. Here, we propose a method to efficiently calculate the second-order NAC from time-dependent density functional theory (TDDFT), on the basis of the Casida ansatz adapted for the computation of first-order NA...

Compared to isolated C$_{60}^{3-}$ ions, characterized by a threedimensional equipotential trough at the bottom of lowest adiabatic potential energy surface (APES), Jahn-Teller (JT) effect in cubic fullerides is additionally influenced interaction JT distortions C$_{60}$ sites with vibrational modes lattice. This leads modification stabilization and warping each fullerene site, as well differen...

In the present paper we report on an analysis of the fine structure of the first excited quartet T2g of Mn4+ ions which occupy the octahedral site in the Cs2GeF6 host crystal. The dynamic T2g⊗ (eg + t2g) Jahn–Teller effect is considered in details, including the Ham effect of the reduction of the spin-orbit splitting and displacements of the ligands due to the combined effect of the a1g and eg ...

The nonlocal and topological nature of the molecular AharonovBohm (MAB) effect is examined for real electronic Hamiltonians. A notion of preferred gauge for MAB is suggested. The MAB effect in the linear + quadratic E ⊗ ε Jahn-Teller system is shown to be essentially analogues to an anisotropic Aharonov-Casher effect for an electrically neutral spin− 2 particle encircling a certain configuratio...

The spin Hamiltonian parameters for the two Cu centers A1 and A2 in the calcined catalysts CuO–ZnO are theoretically investigated using the high order perturbation formulas of these parameters for a 3d ion in tetragonally elongated octahedra. In the above formulas, the tetragonal field parameters Ds and Dt are determined from the superposition model, by considering the relative axial elongation...