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Multi-step phase transition crystal with dielectric constant bistability and temperature-dependent conductivity.

ABSTRACT: Here, we report the crystal structures, phase transitions, and thermal, dielectric, and conducting properties of an ion-pair compound [C₄-bmim][Ni(mnt)₂] (1). 1 undergoes a three-step phase transition with four phases before melting. A two-step dielectric constant bistability is also realized by the structural phase transition in 1 occurring among phases I, II, and III, which is due to the in-plane oscillations of the alkyl chain and crystal-to-mesophase transition, respectively. Moreover, 1 exhibits rare temperature-dependent conducting properties accompanying structural phase transitions, and conductivity is very high with 0.00186 S cm^-1 at 413 K. The conduction properties of phase III (mesophase) arise from the dipole molecular motion.

SUBMITTER: Feng WB

PROVIDER: S-EPMC9661182 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Multi-step phase transition crystal with dielectric constant bistability and temperature-dependent conductivity.

Feng W B WB Xu W W Duan H B HB Zhang H H

RSC advances 20221114 50

Here, we report the crystal structures, phase transitions, and thermal, dielectric, and conducting properties of an ion-pair compound [C4-bmim][Ni(mnt)2] (1). 1 undergoes a three-step phase transition with four phases before melting. A two-step dielectric constant bistability is also realized by the structural phase transition in 1 occurring among phases I, II, and III, which is due to the in-plane oscillations of the alkyl chain and crystal-to-mesophase transition, respect ...[more]

PMID: 36425677

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