title: Negative thermal expansion induced by intermetallic charge transfer.
abstract: Suppression of thermal expansion is of great importance for industry. Negative thermal expansion (NTE) materials which shrink on heating and expand on cooling are therefore attracting keen attention. Here we provide a brief overview of NTE induced by intermetallic charge transfer in A-site ordered double perovskites SaCu3Fe4O12and LaCu3Fe4-xMnxO12, as well as in Bi or Ni substituted BiNiO3. The last compound shows a colossal dilatometric linear thermal expansion coefficient exceeding -70 × 10-6K-1near room temperature, in the temperature range which can be controlled by substitution.
authors.affiliation: Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Azuma
authors.affiliation: Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.
authors.forename: Kengo
authors.initials: K
authors.lastname: Oka
authors.affiliation: Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Nabetani
keywords: charge transfer; negative thermal expansion; perovskite; x-ray diffraction