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Raman scattering, X-ray photoemission spectra and superconductivity of a tiny Ag diffusion to MgCNi3

Fa-Min Liu·J. Q. Li·C. Dong·T. M. Wang·Y. Q. Zhou·H. Chen
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Abstract

The tiny Ag diffusion to MgCNi3 has been prepared by solid states reaction. Its structure was characterized by X-ray diffractometer (XRD). The results show that a small mount of Ag substitute for Ni sites, and much of Ag are in vacancy sites of the MgCNi3. We have further studied the surface properties of Ag-MgCNi3 using Raman scattering spectra, and X-ray photoemission spectra (XPS). Raman spectroscopy shows that the Ag-MgCNi3 has a special Raman peak around 842.1 cm-1 compared to that of C. The superconductor transition temperature (about 6.6 K) of Ag-MgCNi3 was lower than that of pure MgCNi3. It was interpreted properly by the conventional BCS phonon mechanism.

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Fa-Min Liu, J. Q. Li, C. Dong, T. M. Wang, Y. Q. Zhou, H. Chen. 2002-04-25. Raman scattering, X-ray photoemission spectra and superconductivity of a tiny Ag diffusion to MgCNi3. https://arxiv.org/abs/cond-mat/0204543

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