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arXiv · 0812.1911

Fermi surface of MoO2 studied by angle-resolved photoemission spectroscopy, de Haas-van Alphen measurements, and electronic structure calculations

Judith Moosburger-Will·Joerg Kuendel·Matthias Klemm·Siegfried Horn·Philip Hofmann·Udo Schwingenschloegl·Volker Eyert
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Abstract

A comprehensive study of the electronic properties of monoclinic MoO2 from both an experimental and a theoretical point of view is presented. We focus on the investigation of the Fermi body and the band structure using angle resolved photoemission spectroscopy, de Haas-van Alphen measurements, and electronic structure calculations. For the latter, the new full-potential augmented spherical wave (ASW) method has been applied. Very good agreement between the experimental and theoretical results is found. In particular, all Fermi surface sheets are correctly identified by all three approaches. Previous controversies concerning additional hole-like surfaces centered around the Z- and B-point could be resolved; these surfaces were an artefact of the atomic-sphere approximation used in the old calculations. Our results underline the importance of electronic structure calculations for the understanding of MoO2 and the neighbouring rutile-type early transition-metal dioxides. This includes the low-temperature insulating phases of VO2 and NbO2, which have crystal structures very similar to that of molybdenum dioxide and display the well-known prominent metal-insulator transitions.

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Judith Moosburger-Will, Joerg Kuendel, Matthias Klemm, Siegfried Horn, Philip Hofmann, Udo Schwingenschloegl, Volker Eyert. 2009-02-07. Fermi surface of MoO2 studied by angle-resolved photoemission spectroscopy, de Haas-van Alphen measurements, and electronic structure calculations. https://doi.org/10.1103/physrevb.79.115113

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