Negative thermal expansion induced by intermetallic charge transfer.

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 SaCuFeO and LaCuFe Mn O, as well as in Bi or Ni substituted BiNiO.