@article{9d12739c9aef4dcfa6d38890f5815286,
title = "High-Pressure Synthesis of the Cobalt Pyrochlore Oxide Pb2Co2O7 with Large Cation Mixed Occupancy",
abstract = "The novel A2B2O7-type compound Pb2Co2O7 was synthesized at 8 GPa and 1673 K. Synchrotron X-ray diffraction shows a cubic pyrochlore structure with space group Fd3m. Rietveld structural analysis reveals a large cation mixed occupancy at both A and B sites by about 40%, the greatest value found in the pyrochlore family. In combination with the X-ray absorption spectroscopy results, the specific chemical composition and charge states are determined to be (Co0.6Pb0.4)3+2(Pb0.6Co0.4)4+2O7, in which both the A-site Co3+ and the B-site Co4+ are low-spin. Due to the tetrahedral geometric frustration effects as well as the random Co4+ and Pb4+ distribution at the B site, spin glassy behavior is well observed following the conventional critical slowing down feature in Pb2Co2O7.",
author = "Junye Yang and Jianhong Dai and Zhehong Liu and Runze Yu and Hajime Hojo and Zhiwei Hu and Tunwen Pi and Yunliang Soo and Changqing Jin and Masaki Azuma and Youwen Long",
note = "Funding Information: The authors thank L. X. Li for structural determination and fruitful discussions. This work was supported by the 973 Project of the Ministry of Science and Technology of China (Grant No. 2014CB921500), the National Natural Science Foundation of China (Grant Nos. 11574378, 51772324, and 61404052), and the Chinese Academy of Sciences (Grant Nos. QYZDB-SSW-SLH013, XDB07030300, YZ201555, and GJHZ1773). M. Azuma was supported by Kanagawa Institute of Industrial Science and Technology. Y. Long was partially supported by World Research Hub Initiative, Institute of Innovative Research, Tokyo Institute of Technology and Collaborative Research Projects, Laboratory for Materials and Structures, Tokyo Institute of Technology. Publisher Copyright: {\textcopyright} 2017 American Chemical Society.",
year = "2017",
month = oct,
day = "2",
doi = "10.1021/acs.inorgchem.7b01646",
language = "English",
volume = "56",
pages = "11676--11680",
journal = "Inorganic Chemistry",
issn = "0020-1669",
publisher = "American Chemical Society",
number = "19",
}