Geometric Frustration Suppresses Long-Range Structural Distortions in Nb x V 1– x O 2

• Published in: Journal of physical chemistry. C 2022-02, Vol.126 (4), p.2049-2061
• Main Authors: Rawot Chhetri, Top B., Douglas, Tyra C., Davenport, Matthew A., Rosenkranz, Stephan, Osborn, Raymond, Krogstad, Matthew J., Allred, Jared M.
• Format: Article
• Language: English
• Subjects: CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; crystal growth; crystal structure; crystallography; diffuse scattering; geometric frustration; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; lattices; low-dimensional ordering; MATERIALS SCIENCE; metal to insulator transition; metal to insulator transitions; NbO2; NbxV1-xO2; oxides; phase transition; resistivity; scattering; total x-ray scattering; V1-xMoxO2; VO2
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.1c08392

This work provides a detailed overview of compounds with the chemical formulas NbxV1-xO2 (0 ≤ x < 1), including updated synthesis of single crystals and characterization of their physical structures and properties. New structural phases were uncovered and electronic properties were revised. The results together show that the most commonly accepted explanations for the physical properties in these compounds are likely incorrect. In those models, it was assumed that bonds between metal atoms were weakened whenever V is alloyed with metals such as Nb, Mo, and W due to the transfer of electrons between different metallic elements. Besides ruling that model out, this work found that the same geometric frustration model that was recently applied to the V1-xMoxO2 system also applies here. These findings further substantiate the recently proposed geometric frustration model and provide additional details on its mechanism. Understanding this mechanism is expected to lead to improvements in understanding the fundamental science that drives the special materials properties in the broader class of materials.