We report on a measurement of Spin Density Matrix Elements (SDMEs) in hard exclusive
Detailed electrical and photoemission studies were carried out to probe the chemical nature of the insulating ground state of VO_{2}, whose properties have been an issue for accurate prediction by common theoretical probes. The effects of a systematic modulation of oxygen overstoichiometry of VO_{2}from 1.86 to 2.44 on the band structure and insulator–metal transitions are presented for the first time. Results offer a different perspective on the temperature and dopinginduced IMT process. They suggest that charge fluctuation in the metallic phase of intrinsic VO_{2}results in the formation of e^{−}and h^{+}pairs that lead to delocalized polaronic V^{3+}and V^{5+}cation states. The metaltoinsulator transition is linked to the cooperative effects of changes in the V–O bond length, localization of V^{3+}electrons at V^{5+}sites, which results in the formation of V^{4+}–V^{4+}dimers, and removal of
 Award ID(s):
 1709649
 NSFPAR ID:
 10198016
 Publisher / Repository:
 Nature Publishing Group
 Date Published:
 Journal Name:
 Scientific Reports
 Volume:
 10
 Issue:
 1
 ISSN:
 20452322
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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