Pressure effect on intersite charge transfer in A-site-ordered double-perovskite-structure oxide

Long, Y.-W.*; Kawakami, Takateru*; Chen, W.-T.*; Saito, Takashi*; Watanuki, Tetsu; Nakakura, Yuta*; Liu, Q.-Q.*; Jin, C.-Q.*; Shimakawa, Yuichi*

Chemistry of Materials, 24(11), p.2235 - 2239, 2012/06

https://doi.org/10.1021/cm301267e

An A-site ordered perovskite-structure oxide, LaCuFeO, shows unusual intermetallic charge transfer between the A-site Cu and the B-site Fe ions. Like temperature, pressure also induces the intermetallic charge transfer at room temperature and the compound changes from low-pressure LaCuFeO to high-pressure LaCuFeO accompanying with significant volume collapse and as well as unusual softening in bulk modulus. In addition, the material was changed from an antiferromagnetic insulator to a paramagnetic metal transition. Either by physical or chemical (cation substitution) pressure, the charge-transfer transition temperature decreases, and the lower volume phase stabilizes Cu and Fe at the A and B sites, respectively.