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Ab-initio Phonon Calculations for the layered compound TiOCl

Leonardo Pisani·Roser Valenti
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Abstract

We present first-principles frozen-phonon calculations for the three Raman-active $A_g$ modes in the spin-1/2 layered TiOCl system within two different well-known approaches: the local density approximation (LDA) and the so-called LDA+U approximation. We observe that the inclusion of electron correlation in a mean-field level as implemented in the LDA+U leads to a better overall agreement with experimental results. We also discuss the implications of the two approaches on the physics of TiOCl.

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Leonardo Pisani, Roser Valenti. 2005-04-26. Ab-initio Phonon Calculations for the layered compound TiOCl. https://doi.org/10.1103/physrevb.71.180409

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