Orbital Dimerization and Dynamic Jahn-Teller Effect in NaTiSi$_2$O$_6$

Details Orbital Dimerization and Dynamic Jahn-Teller Effect in NaTiSi$_2$O$_6$ Orbital Dimerization and Dynamic Jahn-Teller Effect in NaTiSi$_2$O$_6$

2002-10-09

arxiv.org/abs/cond-mat/0210191v2

Physics

Condensed Matter

Strongly Correlated Electrons

4 pages, 4 figures embedded

Scientific paper

We study with the Raman scattering technique two types of phase transitions in the pyroxene compounds NaMSi$_2$O$_6$ (with M=Ti, V, and Cr). In the quasi one-dimensional S=1/2 system NaTiSi$_2$O$_6$ we observe anomalous high-temperature phonon broadening and large changes of the phonon energies and line-widths across the phase transition at 210 K. The phonon anomalies originate from an orbital order-disorder phase transition and these results --combined with theoretical considerations-- indicate that the high temperature dynamical Jahn-Teller phase of NaTiSi$_2$O$_6$ exhibits a spontaneous breaking of translational symmetry into a dimerized, Jahn-Teller distorted, orbital ordered state under the formation of spin valence bonds. In S=1 NaVSi$_2$O$_6$ orbital degrees of freedom are strongly suppressed and the magnetic excitations are well described within a Heisenberg model, indicating that at T$_N$=19K this system orders antiferromagnetically.

Affiliated with

Also associated with

No associations

Rating

Orbital Dimerization and Dynamic Jahn-Teller Effect in NaTiSi$_2$O$_6$ does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Orbital Dimerization and Dynamic Jahn-Teller Effect in NaTiSi$_2$O$_6$, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Orbital Dimerization and Dynamic Jahn-Teller Effect in NaTiSi$_2$O$_6$ will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-204439