Polarized X-ray absorption spectroscopic experiments have been carried out for the mercuric bromide intercalated Bi2Sr2CaCu2Oysingle crystal, in order to understand the variation of anisotropic resistivities upon HgBr2intercalation as well as to probe the electronic structure of HgBr2intercalate. The Br K- and Bi Lin-edge spectra indicate a significant electron transfer from bismuth to bromine, implying an overlap between Bi 6s and Br 4p orbitals. From the Hg LIII- and Br K-edge data, it is also found that HgBr2intercalation gives rise to an electron localization in the (Hg-Br) bond, which leads to poor electronic conduction along the intercalant layer. In this context, the semiconducting out-of-plane resistivity of HgBr2intercalate can be explained by the poor conductivity of the intercalated HgBr2layer, even though the orbital overlap between Bi and Br facilitates the electron conduction between host and guest along the c-axis.
Bibliographical noteFunding Information:
This work was supported in part by the Korean Ministry of Science and Technology through the 1999 National Research Laboratory (NRL) project and in part by the Korean Ministry of Education through the Brain Korea 21 program. The authors are also grateful to Prof. M. Nomura for helping us to get the XAS data in the Photon Factory.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry