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High Pressure X-Ray Diffraction Study of UMn2Ge2

Vasudeva Siruguri·S. K. Paranjpe·P. Raj·A. Sathyamoorthy·Jean Paul Itie·Alain Polian
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Abstract

Uranium manganese germanide, UMn2Ge2, crystallizes in body-centered tetragonal ThCr2Si2 structure with space group I4/mmm, a = 3.993A and c = 10.809A under ambient conditions. Energy dispersive X-ray diffraction was used to study the compression behaviour of UMn2Ge2 in a diamond anvil cell. The sample was studied up to static pressure of 26 GPa and a reversible structural phase transition was observed at a pressure of ~ 16.1 GPa. Unit cell parameters were determined up to 12.4 GPa and the calculated cell volumes were found to be well reproduced by a Murnaghan equation of state with K0 = 73.5 GPa and K' = 11.4. The structure of the high pressure phase above 16.0 GPa is quite complicated with very broad lines and could not be unambiguously determined with the available instrument resolution.

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Vasudeva Siruguri, S. K. Paranjpe, P. Raj, A. Sathyamoorthy, Jean Paul Itie, Alain Polian. 2004-07-29. High Pressure X-Ray Diffraction Study of UMn2Ge2. https://doi.org/10.1016/j.physb.2003.09.267

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