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Title: IrGe 4 : A Predicted Weyl-Metal with a Chiral Crystal Structure
Polycrystalline IrGe4 was synthesized by annealing elements at 800 °C for 240 h, and the composition was confirmed by energy-dispersive X-ray spectroscopy. IrGe4 adopts a chiral crystal structure (space group P3121) instead of a polar crystal structure (P31), which was corroborated by the convergent-beam electron diffraction and Rietveld refinements using synchrotron powder X-ray diffraction data. The crystal structure features layers of IrGe8 polyhedra along the b axis, and the layers are connected by edge- and corner-sharing. Each layer consists of corner-shared [Ir3Ge20] trimers, which are formed by three IrGe8 polyhedra connected by edge-sharing. Temperature-dependent resistivity indicates metallic behavior. The magnetoresistance increases with increasing applied magnetic field, and the nonsaturating magnetoresistance reaches 11.5% at 9 T and 10 K. The Hall resistivity suggests that holes are the majority carrier type, with a carrier concentration of 4.02 × 1021 cm–3 at 300 K. Electronic band structures calculated by density functional theory reveal a Weyl point with a chiral charge of +3 above the Fermi level.  more » « less
Award ID(s):
2143903 2343536
PAR ID:
10517711
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Inorganic Chemistry
Date Published:
Journal Name:
Inorganic Chemistry
Volume:
62
Issue:
48
ISSN:
0020-1669
Page Range / eLocation ID:
19395 to 19403
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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