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arXiv · 1409.3333

Multiferroic CuCrO2 under High Pressure: In-Situ X-Ray Diffraction and Raman Spectroscopic Studies

Alka B. Garg·A. K. Mishra·K. K. Pandey·Surinder M. Sharma
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Abstract

The compression behavior of delafossite compound CuCrO2 has been investigated by in-situ x-ray diffraction and Raman spectroscopic measurements upto 23.2 and 34 GPa respectively. X-ray diffraction data shows the stability of ambient rhombohedral structure upto ~ 23 GPa. Material shows large anisotropy in axial compression with c-axis compressibility, c= 1.2610-3(1) GPa-1 and a-axis compressibility, a= 8.9010-3(6) GPa-1. Our XRD data shows an irreversible broadening of diffraction peaks. Pressure volume data when fitted to 3rd order Birch-Murnaghan equation of state gives the value of bulk modulus, B0 = 156.7(2.8) GPa with its pressure derivative, B0' as 5.3(0.5). All the observed vibrational modes in Raman measurements show hardening with pressure. Appearance of a new mode at ~24 GPa indicates the structural phase transition in the compound. Our XRD and Raman results indicate that CuCrO2 may be transforming to an ordered rocksalt type structure under compression.

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Alka B. Garg, A. K. Mishra, K. K. Pandey, Surinder M. Sharma. 2014-09-11. Multiferroic CuCrO2 under High Pressure: In-Situ X-Ray Diffraction and Raman Spectroscopic Studies. https://doi.org/10.1063/1.4896952

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