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arXiv · 1104.4922

Spin-Peierls transition in TiPO$_4$

J. M. Law·C. Hoch·R. Glaum·I. Heinmaa·R. Stern·J. Kang·C. Lee·M. -H. Whangbo·R. K. Kremer
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Abstract

We investigated the magnetic and structural properties of the quasi-one dimensional 3$d^1$-quantum chain system TiPO$_4$ ($J \sim$ 965 K) by magnetic susceptibility, heat capacity, ESR, x-ray diffraction, NMR measurements, and by density functional calculations. TiPO$_4$ undergoes two magnetostructural phase transitions, one at 111 K and the other at 74 K. Below 74 K, NMR detects two different $^{31}$P signals and the magnetic susceptibility vanishes, while DFT calculations evidence a bond alternation of the Ti...Ti distances within each chain. Thus, the 74 K phase transition is a spin-Peierls transition which evolves from an incommensurate phase existing between 111 K and 74 K.

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J. M. Law, C. Hoch, R. Glaum, I. Heinmaa, R. Stern, J. Kang, C. Lee, M. -H. Whangbo, R. K. Kremer. 2011-04-26. Spin-Peierls transition in TiPO$_4$. https://doi.org/10.1103/physrevb.83.180414

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