Berlin 2024 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
DS: Fachverband Dünne Schichten
DS 15: Thermoelectric and Phase Change Materials
DS 15.1: Talk
Thursday, March 21, 2024, 10:30–10:45, A 060
Force constants and bond strength in elemental electron rich Sb — •Franziska Zahn1, Christopher Benndorf2, Hans H. Falk1, Konrad Ritter1, Eva M. Zollner1, Sergiu Levcenko1, Edmund Welter3, Oliver Oeckler2, and Claudia S. Schnohr1 — 1Felix Bloch Institute for Solid State Physics, Leipzig University, Germany — 2Institute of Mineralogy, Crystallography and Materials Science, Leipzig University, Germany — 3Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
The valence-electron count of the group V metalloid Sb is 5, corresponding to an electron rich system similar to many thermoelectric and phase change materials such as GeTe and PbTe. Elemental Sb exhibits a layered structure, where each Sb atom has three short and three slightly longer first neighbor bonds. To study the structural and vibrational properties of Sb in more detail, extended X-ray absorption fine structure spectroscopy (EXAFS) was performed at the Sb K-edge at ten different temperatures ranging from 20 K to 295 K. The temperature dependence of the bond length variation σ2 (mean square relative displacement) was evaluated using a correlated Einstein model, providing static disorder and bond-stretching force constants. Interestingly, the force constant of the long first neighbor bond is ∼2.5 times lower than that of the short first neighbor bond, but similar to the force constants of the second neighbor bonds. These results are compared to those of first and higher neighbor bonds in metallic Cu, Ge with a classical covalent bonding and GeTe, thus contributing to the understanding of bonding in Sb as an elemental electron rich system.
Keywords: antimony; bonding; force constants; atomic vibrations; X-ray absorption spectroscopy