title: Thermodynamic investigation of the charge-ordered insulating state of the quasi-one-dimensional organic system (DI-DCNQI)2Ag.
abstract: Heat capacity measurements of a charge-ordered organic conductor (DI-DCNQI)2Ag have been performed in a temperature range between 0.3 and 14 K. We found no thermal anomaly at the Néel temperature ( T(N) = 5.5 K) but instead a T-linear term suggestive of the spin excitations of one-dimensional character in the charge-ordered insulating state. The analysis of the T-linear term and the excess entropy indicates that the charge fluctuations in the charge-ordered state influence the growth of spin excitations at elevated temperatures, which seems to be a peculiar aspect of a 1D charge-ordered system.
authors.affiliation: Research Center for Molecular Thermodynamics, Osaka University, Machikaneyama 1-1, Toyonaka, Osaka 560-0043, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nakazawa
authors.forename: Mitsuro
authors.initials: M
authors.lastname: Seki
authors.forename: Kazuya
authors.initials: K
authors.lastname: Saito
authors.forename: Ko-ichi
authors.initials: K
authors.lastname: Hiraki
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Takahashi
authors.forename: Kazushi
authors.initials: K
authors.lastname: Kanoda
authors.forename: Michio
authors.initials: M
authors.lastname: Sorai