X-ray absorption spectroscopy on the phase transition of Cd$_{2}$Re$_{2}$O$_{7}$

Pyrochlore Cd$_{2}$Re$_{2}$O$_{7}$ has received considerable attention and investigated extensively because of its manifold phase transitions accompanied by profound physical properties. In this study, the relations among the electronic structure, phase transition, and some physical properties of Cd$_{2}$Re$_{2}$O$_{7}$ single crystals have been investigated. We conducted the X-ray diffraction as well as Re $L_{2,3}$-edge extended X-ray absorption fine structure (EXAFS) at different temperatures to investigate the local structure of Cd$_{2}$Re$_{2}$O$_{7}$ and temperature-dependent O $K$-edge X-ray absorption near edge structure (XANES) to probe its electronic structure during the phase transition. We also performed the band structure calculations to understand the DOS near the Fermi level of Cd$_{2}$Re$_{2}$O$_{7}$ at different temperatures.