Vibrational dynamics of the host framework in Sn clathrates

Article

关键词: FILLED SKUTTERUDITE ANTIMONIDES;    RAMAN-SPECTROSCOPY;    CRYSTAL-STRUCTURE;    COMPOUND;    SCATTERING;    IRON;    SUPERCONDUCTIVITY;    PROTEIN;   

DOI  :  10.1103/PhysRevB.90.104304

来源: SCIE

【 摘 要 】

We use nuclear resonance inelastic x-ray scattering (NRIXS), a relatively new, synchrotron-based, isotopespecific technique in combination with a more traditional one, Raman spectroscopy, to probe the vibrational dynamics of the host frameworks in two Zintl clathrates: K8Zn4Sn42 (KZS) and Ba8Ga16Sn30 (BGS). From the normalized Sn vibrational density of states obtained from NRIXS, we calculate the stiffness, a mean force constant of the Sn environment, the resilience, a compact way of expressing the temperature dependence of the Sn mean square displacement, and several thermodynamic properties. The stiffness and the resilience are approximately 7% lower in KZS, reflecting its larger unit cell compared to BGS. We emphasize the complementariness between NRIXS and Raman spectroscopy and establish a series of benchmarks for a more quantitative evaluation of the Raman spectra for the numerous clathrates that are still not suitable for NRIXS studies.

【 授权许可】

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