Mesophases and ionic conductivities of simple organic salts of M(m-iodobenzoate) (M = Li+, Na+, K+, Rb+, and Cs+)

Manami Endo, Yuta Nakane, Kiyonori Takahashi, Norihisa Hoshino, Takashi Takeda, Shin Ichiro Noro, Takayoshi Nakamura, Tomoyuki Akutagawa

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)

Abstract

Simple organic salts such as (Li+)(m-IBA) (1), (Na+)(m-IBA) (2), (K+)(m-IBA) (3), (Rb+)(m-IBA) (4), and (Cs+)(m-IBA) (5) (m-IBA = m-iodobenzoate) were shown to form a mesophase before crystal melting or decomposition. The crystals were obtained in the hydrated form, e.g., 1·(H2O), 2· (H2O), 3·0.5(H2O), 4·(H2O), and 5·(H2O); they were then converted into dehydrated forms by increasing the temperature to ∼450 K. Optically anisotropic-layered mesophases were observed in unhydrated crystals 2, 3, 4, and 5, whereas an optically isotropic mesophase (e.g., rotator phase) was found for crystal 1. The single-crystal X-ray structural analysis of the hydrated crystals revealed an inorganic-organic alternate layer structure, which is consistent with the average molecular orientation in the layered mesophase. The m-IBA anions formed a π-stacking columnar structure in the hydrated crystals, while one- or two-dimensional M+∼O networks were observed in the inorganic layers. Our results showed that the M+∼ O interactions and their connectivity are strongly influenced by the size of the cations. The reconstruction of the M+∼O networks by removing H2O molecules was crucial for the formation of the mesophases. A strong response of both the real and imaginary parts of the dielectric constant was observed around the solid-mesophase phase-transition temperatures of crystals 1-5, with the ionic conductions playing a critical role.(Figure Presented).

Original languageEnglish
Pages (from-to)1768-1777
Number of pages10
JournalJournal of Physical Chemistry B
Volume119
Issue number4
DOIs
Publication statusPublished - 2015 Jan 29

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Mesophases and ionic conductivities of simple organic salts of M(m-iodobenzoate) (M = Li<sup>+</sup>, Na<sup>+</sup>, K<sup>+</sup>, Rb<sup>+</sup>, and Cs<sup>+</sup>)'. Together they form a unique fingerprint.

Cite this