Journal of Thermal Analysis and Calorimetry

, Volume 108, Issue 2, pp 399–413

The role of calorimetry in the structural study of mesophases and their glass states

  • F. J. Martínez Casado
  • M. Ramos Riesco
  • M. I. Redondo Yélamos
  • A. Sánchez Arenas
  • J. A. Rodríguez Cheda
Article

DOI: 10.1007/s10973-011-1938-2

Cite this article as:
Martínez Casado, F.J., Ramos Riesco, M., Redondo Yélamos, M.I. et al. J Therm Anal Calorim (2012) 108: 399. doi:10.1007/s10973-011-1938-2

Abstract

Four mesomorphic states of matter are known: liquid crystal, plastic crystal, condis phase, and rotator phase, all of them are solid phases, except liquid crystal, which is fluid. Plastic crystal (also called ODIC, orientational disordered crystal), rotator phase, and even condis phase have been considered the same phase by many authors. Differences between them will be established to define their own characteristics. Two organic salts series have been used for discussion in this presentation: (1) thallium(I) alkanoate series, that presents a condis mesophase, and (2) lead(II) alkanoate series, that present a rotator one, both forming a smectic A-like liquid crystal phase. Based in the literature data of the alkyl ammonium bromide series it can be established that the short chain length members would present a rotator phase, and, the large chain ones, a condis phase. Five different glass states are known (four with partial crystalline order), corresponding with the above mentioned mesophases, and the ordinary (amorphous) glass state.

Keywords

Organic salts Thallium(II) alkanoates Lead(II) alkanoates DSC TG Adiabatic calorimetry FTIR Powder XRD Single crystal XRD NMR Mesophases Liquid crystal ODIC Plastic crystal Rotator phase Condis phase Amorphous glass Plastic crystal glass Liquid crystal glass Rotator glass Condis glass Step-wise melting process 

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2011

Authors and Affiliations

  • F. J. Martínez Casado
    • 1
  • M. Ramos Riesco
    • 2
  • M. I. Redondo Yélamos
    • 2
  • A. Sánchez Arenas
    • 3
  • J. A. Rodríguez Cheda
    • 2
  1. 1.Laboratorio de Estudios CristalográficosIACT (CSIC-UGR)GranadaSpain
  2. 2.Departamento de Química Física I, Facultad de Ciencias QuímicasUniversidad ComplutenseMadridSpain
  3. 3.Sección Departamental de Física Aplicada I, Facultad de VeterinariaUniversidad ComplutenseMadridSpain

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