Universal thermal response of the Prussian blue lattice

作者：Matsuda T; Kim J E; Ohoyama K; Moritomo Y^*

来源：Physical Review B, 2009, 79(17): 172302.

DOI：10.1103/PhysRevB.79.172302

• organic compounds
• stability
• thermal expansion
• X-ray diffraction

Thermal responses of Prussian blue lattice, that is, a rocksalt-type network of metal ions bridged by cyano group, are systematically investigated for (Cs,Rb)(x)M(II)[Fe(III)(CN)(6)](y)zH(2)O (M=Ni, Cu, Zn, and Cd) and (Cs,Rb)(x)M(III)[Fe(II)(CN)(6)](y)zH(2)O (M=Fe and Co) by means of the synchrotron-radiation x-ray powder diffraction. We found a universal relation between the coefficient (beta equivalent to d ln a/dT; a is lattice constant) of the thermal expansion and magnitude of a: beta changes the sign from positive to negative with increase in a. We ascribed the negative thermal expansion observed in the large-a region to intrinsic rotational instability of the [Fe(CN)(6)] unit.

• 出版日期2009-5