Detailed mapping of the local Ir{sup 4+} dimers through the metal-insulator transitions of CuIr{sub 2}S{sub 4} thiospinel by x-ray atomic pair distribution function measurements.
The evolution of the short-range structural signature of the Ir{sup 4+} dimer state in CuIr{sub 2}S{sub 4} thiospinel has been studied across the metal-insulator phase transitions as the metallic state is induced by temperature, Cr doping, and x-ray fluence. An atomic pair distribution function (PDF) approach reveals that there are no local dimers that survive into the metallic phase when this is invoked by temperature and doping. The PDF shows Ir{sup 4+} dimers when they exist, regardless of whether or not they are long-range ordered. At 100 K, exposure to a 98 keV x-ray beam melts the long-range dimer order within a few seconds, though the local dimers remain intact. This shows that the metallic state accessed on warming and doping is qualitatively different from the state obtained under x-ray irradiation.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- DE-AC02-06CH11357
- OSTI ID:
- 1004055
- Report Number(s):
- ANL/MSD/JA-68940; TRN: US201103%%300
- Journal Information:
- Phys. Rev. Lett., Vol. 106, Issue Jan. 24, 2011
- Country of Publication:
- United States
- Language:
- ENGLISH
Similar Records
Metal-insulator transition in the spinel-type Cu{sub 1-x}Ni{sub x}Ir{sub 2}S{sub 4} system
Phase separation at the dimer-superconductor transition in Ir1-xRhxTe2