Thermal expansion of filled skutterudite compound GdRu4P 12

Abstract

We have performed X-ray diffraction and thermal expansion measurements at low temperatures of the filled skutterudite compound GdRu4P 12 in order to investigate structural changes related to the antiferromagnetic phase transition at TN=22K. No significant change in the X-ray powder diffraction pattern of GdRu4P12 was detected down to 10K. The variation of thermal expansion is continuous at T N. Therefore, the transition is not accompanied with any crystallographic transformation. The temperature dependence of the linear thermal expansion coefficient shows large jump (1.2 × 10-6 K-1) at TN. This value is comparable to that of isostructual compound SmRu4P12 at the metal-insulator transition temperature TMI=16K. © 2009 IOP Publishing Ltd.