Structural, Magnetic and Electrical Transport Properties of Ternary Compound LaCo₂Ge₂

Abstract:

Ternary compound LaCo₂Ge₂ was synthesized and characterized by means of XRD, magnetic and electrical measurements. Rietveld structure refinements of powder XRD patterns confirm that LaCo₂Ge₂ compound crystallizes with a body-centered tetragonal structure of ThCr₂Si₂-type (space group I4/mmm) with the unit lattice parameters a=4.105(6) Å and c=10.264(7) Å. Nd, Co and Ge occupy 2a, 4d and 4e crystal positions, respectively. Magnetism measurements show that LaCo₂Ge₂ is nearly temperature-impendent Pauli paramagnetic down to 100 K, whereas orders diamagnetic at elevated temperatures. The (T) measurement showed that is 0.34625 and a positive temperature coefficient for LaCo₂Ge₂ is equal to 0.82178, indicating that LaCo₂Ge₂ exhibits typical semimetallic.

• Periodical: Applied Mechanics and Materials (Volume 455)
• Pages: 148-153
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.455.148
• Online since: November 2013
• Authors: Han Yuan Liu, Li Fu, Yong Quan Guo
• Keywords: LaCo₂Ge₂, Pauli Paramagnetic, Rietveld Refinement, Semimetallic, Structure

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