Orientational Ordering of Octahedral Anions in the Organic Conductor (TMTSF)₂SbCl₂F₄

Abstract

An orientational ordering of octahedral anions was found below about 180 K in the quasi one-dimensional conductor (TMTSF)₂SbCl₂F₄. The ordered anions having electric dipole moments form a superstructure which doubles the unit cell along the b-axis, the direction nearly perpendicular to the one-dimensional axis. Possible inferrelation is discussed between the ordered structure and electrical properties, especially the superconductivity found in several salts belonging to the family of (TMTSF)₂X.