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arXiv · 0704.0170

Symmetry disquisition on the TiOX phase diagram

Daniele Fausti·Tom T. A. Lummen·Cosmina Angelescu·Roberto Macovez·Javier Luzon·Ria Broer·Petra Rudolf·Paul H. M. van Loosdrecht·Natalia Tristan·Bernd Buchner·Sander van Smaalen·Angela Moller·Gerd Meyer·Timo Taetz
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Abstract

The sequence of phase transitions and the symmetry of in particular the low temperature incommensurate and spin-Peierls phases of the quasi one-dimensional inorganic spin-Peierls system TiOX (TiOBr and TiOCl) have been studied using inelastic light scattering experiments. The anomalous first-order character of the transition to the spin-Peierls phase is found to be a consequence of the different symmetries of the incommensurate and spin-Peierls (P$2_{1}/m$) phases. The pressure dependence of the lowest transition temperature strongly suggests that magnetic interchain interactions play an important role in the formation of the spin-Peierls and the incommensurate phases. Finally, a comparison of Raman data on VOCl to the TiOX spectra shows that the high energy scattering observed previously has a phononic origin.

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Daniele Fausti, Tom T. A. Lummen, Cosmina Angelescu, Roberto Macovez, Javier Luzon, Ria Broer, Petra Rudolf, Paul H. M. van Loosdrecht, Natalia Tristan, Bernd Buchner, Sander van Smaalen, Angela Moller, Gerd Meyer, Timo Taetz. 2007-10-30. Symmetry disquisition on the TiOX phase diagram. https://doi.org/10.1103/physrevb.75.245114

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