不規則性をもつ結晶，超イオン導電体，非晶質，ガラス，融体の構造解析―不規則系・ランダム系の結晶学―１．周期系における不規則性の解析 有機擬一次元物質の秩序無秩序転移と電荷不均一化

Abstract

High resolution X-ray structure analyses revealed the condition for the charge ordering (CO) observed in the quasi one-dimensional compounds (TMTTF) 2X. The size and orientational ordering of the counter anion X control the dimerization and tetramerization of TMTTF molecules. The molecular dimerization suppresses the 4kF CO, while the tetramerization assists the 2kF CO. The phase diagram of the electronic states including 2kF and 4kF CO has been proposed associated with magnitudes of the molecular dimerization and tetramerization.