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Title: Exploring the A-V-Sb landscape beyond AV3Sb5: A case study on the KV6Sb6 Kagome compound
Kagome compounds have garnered attention in the past few years for their intriguing magnetic properties arising from spin frustration dictated by the geometry of the Kagome sublattice. In this paper, we highlight the success of the unconventional hydride route for the fast and easy synthesis of the Kagome compound KV6Sb6. High-temperature in situ powder x-ray diffraction (PXRD) studies proved to be useful in hinting at the existence of KV6Sb6, identifying its synthesis conditions, and understanding the reaction mechanism. The crystal structure for KV6Sb6 was determined from high-resolution PXRD data. The compound has a layered structure [R¯3m,a=5.5318(9)Å, c=34.23(3)Å, V=907.0(8)Å3, Z=3 at room temperature] and features a Kagome bilayer of V atoms. KV6Sb6 is isostructural to the previously reported RbV6Sb6 and CsV6Sb6 compounds. KV6Sb6 is thermally stable in vacuum up to 1173 K, as evident from the high-temperature in situ PXRD and differential scanning calorimetric analysis. Investigation of magnetic properties for KV6Sb6 between 2 and 300 K reveals temperature-independent paramagnetism and an absence of superconductivity, like the Rb and Cs analogs. Furthermore, we compare the magnetic properties of KV3Sb5, another ternary Kagome compound, synthesized via two different methods: the hydride route and the traditional route from elements. Low-temperature transport property measurements of KV6Sb6 indicate metallic behavior and an intrinsically low thermal conductivity of 1.0WK−1m−1 at 300 K. The layered structure of KV6Sb6 makes it an attractive candidate for deintercalation and doping studies to tune both magnetic and transport properties, laying a foundation for further studies.  more » « less
Award ID(s):
1944551
PAR ID:
10487504
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
APS
Date Published:
Journal Name:
Physical Review Materials
Volume:
7
Issue:
11
ISSN:
2475-9953
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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