Strong Negative Thermal Expansion along the O−Cu−O Linkage in CuScO2

• Published in: Chemistry of materials 2002-06, Vol.14 (6), p.2602-2606
• Main Authors: Li, J, Yokochi, A, Amos, T. G, Sleight, A. W
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Inorganic compounds; Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Thermal expansion; thermomechanical effects; Thermal expansion; thermomechanical effects and density; Thermal properties of condensed matter; Thermal properties of crystalline solids; Water, oxides, hydroxides, peroxides
• ISSN: 0897-4756; 1520-5002
• DOI: 10.1021/cm011633v

The structure of 2H CuScO2 has been refined from single-crystal X-ray diffraction data obtained at room temperature and from neutron powder diffraction data obtained from 11 to 1206 K. Strong negative thermal expansion (−4.0 × 10-6/K) has been found for the apparent Cu−O bond length below 300 K. This is the first example of strong negative thermal expansion in a metal oxide based on an O−M−O linkage instead of a M−O−M linkage. It is now the transverse thermal motion of Cu, instead of the transverse thermal motion of oxygen, that causes the negative thermal expansion. As expected for this mechanism for negative thermal expansion, the thermal displacement parameter for Cu is very pronounced perpendicular to the linear O−Cu−O linkage.