2,4,6-Trimethylpyridinium perchlorate: Polar properties and correlations with molecular structure of organic-inorganic hybrid crystal

Journal Article · Sun Nov 15 00:00:00 EST 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.07.055· OSTI ID:21372381

Wojtas, M ^[1]; Gagor, A ^[2]; Czupinski, O ^[1]; Pietraszko, A ^[2]; Jakubas, R ^[1]

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1. Faculty of Chemistry, University of WrocLaw, Joliot-Curie 14, 50-383 WrocLaw (Poland)
2. W. Trzebiatowski Institute of Low Temperature and Structure Research PAS, P.O. box 1410, 50-950 WrocLaw (Poland)

[(CH{sub 3}){sub 3}C{sub 5}H{sub 2}NH][ClO{sub 4}] has been synthesized and characterized by X-ray (at 344, 245, 180 and 115 K), calorimetric, dilatometric, dielectric and pyroelectric measurements. At room temperature the crystal structure is polar, space group Pmn2{sub 1}. It consists of discrete disordered [ClO{sub 4}]{sup -} anions and ordered trimethylpyridinium cations giving the 3D network of hydrogen bonds. The compound reveals a rich polymorphism in the solid state. It undergoes four solid-solid phase transitions: from phases I to II at 356/327 K (heating/cooling), II->III at 346/326, III->IV at 226 K and IV->V at 182/170 K. [(CH{sub 3}){sub 3}C{sub 5}H{sub 2}NH][ClO{sub 4}] reveals a strong pyroelectric response over a wide temperature region (phases III, IV and V) with the spontaneous polarization changes (DELTAP{sub s}) of the order of 1.5-8x10{sup -3}C/m{sup 2}. The spontaneous polarization is irreversible over all the polar phases, however, the magnitude of the DELTAP{sub s} in the vicinity of the phase transitions is characteristic of compounds with the ferroelectric order. The molecular mechanism of the successive phases transitions in the studied crystal is proposed. - A novel organic-inorganic hybrid material, simple ionic salt: 2,4,6-trimethylpyridinium perchlorate, [(CH{sub 3}){sub 3}C{sub 5}H{sub 2}NH][ClO{sub 4}] has been synthesized. In this paper we report singlecrystal X-ray, powder X-ray, calorimetric, dilatometric, dielectric and pyroelectric studies of this compound over a wide temperature range. A possible mechanism of the structural phase transitions in [(CH{sub 3}){sub 3}C{sub 5}H{sub 2}NH][ClO{sub 4}] is discussed with particular attention focused on unusually strong pyroelectric properties.

• OSTI ID: 21372381
• Journal Information: Journal of Solid State Chemistry, Vol. 182, Issue 11; Other Information: DOI: 10.1016/j.jssc.2009.07.055; PII: S0022-4596(09)00363-6; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ANIONS
CALORIMETRY
CATIONS
COOLING
CRYSTAL STRUCTURE
CRYSTALS
FERROELECTRIC MATERIALS
HEATING
MOLECULAR STRUCTURE
PERCHLORATES
PHASE TRANSFORMATIONS
POLARIZATION
PYRIDINES
SPACE GROUPS
TEMPERATURE RANGE 0065-0273 K
TEMPERATURE RANGE 0273-0400 K
X RADIATION
AZINES
CHARGED PARTICLES
CHLORINE COMPOUNDS
DIELECTRIC MATERIALS
ELECTROMAGNETIC RADIATION
HALOGEN COMPOUNDS
HETEROCYCLIC COMPOUNDS
IONIZING RADIATIONS
IONS
MATERIALS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXYGEN COMPOUNDS
RADIATIONS
SYMMETRY GROUPS
TEMPERATURE RANGE