Effect of Anion Disorder on the Peierls Transition in the Commensurate One-Dimensional Conductors (TTF)(SCN)0.56(ClO4)0.01, (TTF)(NO3)0.59(Cl)0.28, and (TTF)(SCN)0.09(Br)0.59

• Published in: The journal of physical chemistry. B 1999-09, Vol.103 (36), p.7565-7572
• Main Authors: Mizuno, Masagi, Honda, Kazumasa, Akimoto, Jyunji, Nakayama, Hikari, Uchida, Tokiko
• Format: Article
• Language: English
• ISSN: 1520-6106; 1520-5207
• DOI: 10.1021/jp990558x

Three new quasi-one-dimensional tetrathiafulvalenium (TTF) conductors, (TTF)(SCN)0.56(ClO4)0.01, (TTF)(NO3)0.59(Cl)0.28, and (TTF)(SCN)0.09(Br)0.59, were obtained by electrochemical crystallization. They are all nonstoichiometric compounds with commensurate anion ratios and behave as Mott's 1D variable range hopping conductors because of their disordered anion structure. Evidenced by their unusual structure−conductivity characteristics, they are considered as in the intermediate regime, ranging from the highly conducting incommensurate compounds to the almost insulating commensurate salts with Peierls structure typified by (TTF)3(BF4)2. The Peierls instability is thus suppressed giving incomplete Peierls structures for these compounds despite their commensurate band filling ratio. This was most probably derived from the random potential exerted over TTF conducting chain by the disordered anion structure.