Possible Charge Ordering Patterns of the Paramagnetic Insulating States in (TMTTF)₂X

Abstract

ESR investigations were performed for a series of quasi-one-dimensional organic conductors, (TMTTF)₂X. The ESR linewidth shows abrupt jumps or humps in the paramagnetic insulating region. The (TMTTF)₂X salts are roughly divided into three groups according to the anisotropy of the ESR linewidth at low temperatures. In this paper, we discuss the possible charge-ordered patterns of three typical salts (X=ReO₄, SbF₆ and Br) from the microscopic point of view.