Jahn-Teller coupling and fragmentation after core-shell excitation ini CF4 investigated by partial-ion-yield spectroscopy

Jahn-Teller Coupling in the X̃ E Ground States of the CF3O and CF3S Radicals

The Jahn-Teller and spin-orbit coupling in the ground states of the CF3O and CF3S radicals have been investigated experimentally by dispersed fluorescence spectroscopy. These spectra are analyzed using a theoretical model that simultaneously includes spin-orbit coupling and multimode Jahn-Teller, both linear and quadratic. We find that in each of these radicals a moderate linear Jahn-Teller eff...

Mössbauer Effect Probe of Local Jahn-Teller distortion in Fe-doped Colossal Magnetoresistive Manganites

Local structure of the Fe-doped La1−xCaxMnO3 (x=0.00-1.00) compounds has been investigated by means of Mössbauer spectroscopy. 57Fe Mössbauer spectra provide a direct evidence of Jahn-Teller distortion in these manganites. On the basis of Mössbauer results, the Jahn-Teller coupling was estimated. It is noteworthy that Ca-concentration dependence of Jahn-Teller coupling strength is very consiste...

Photofragmentation of SiF4 upon Si 2p and F 1s core excitation: cation and anion yield spectroscopy.

We have studied the fragmentation dynamics of core-excited SiF4 by means of soft-x-ray photoexcitation and partial positive and negative ion yield measurements around the Si L2,3-shell and F K-shell ionization thresholds. All detectable ionic fragments are reported and we observe significant differences between the various partial ion yields near the Si 2p threshold. The differences are similar...

Fragmentation processes following core excitation in acetylene and ethylene by partial ion yield spectroscopy

Jahn-Teller effect in the augmented Hubbard model

We investigate the effects induced by the interplay of microscopic degrees of freedom. In many cases, one has to consider spin and orbital degeneracy to explain complex structures of magnetic and orbital order. Frequently, attention is focused on electronic correlations. We study how the interaction of electrons with lattice degrees of freedom modifies the pure electronic case. Because of orbit...