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Mechanism for modulated structures in Ni-Mn-Ga: An EXAFS Study

P. A. Bhobe·K. R. Priolkar·P. R. Sarode
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Abstract

The local atomic structure of Ni-Mn-Ga alloys was explored using Mn and Ga K-edge extended X-ray fine structure (EXAFS) measurement. The changes occuring in the L1$_0$ sub-cell of the martensitic unit cell and the bond lengths obtained from the analysis enables us to propose a scheme for the structural distortions responsible for the modulations and shuffling of the atomic planes in the martensitic phase of Ni-Mn-Ga system. The EXAFS analysis also suggests the changes in hybridization of Ga-$p$ and Ni-$d$ orbitals associated with the local symmetry breaking upon undergoing martensitic transition.

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P. A. Bhobe, K. R. Priolkar, P. R. Sarode. 2006-08-10. Mechanism for modulated structures in Ni-Mn-Ga: An EXAFS Study. https://arxiv.org/abs/cond-mat/0604010

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