Thermodynamic Scaling of the Dynamics of a Strongly Hydrogen-Bonded Glass-Former
Abstract We probe the temperature- and pressure-dependent specific volume (v) and dipolar dynamics of the amorphous phase (in both the supercooled liquid and glass states) of the ternidazole drug (TDZ). Three molecular dynamic processes are identified by means of dielectric spectroscopy, namely the...
Main Authors: | , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Nature Publishing Group
2017-05-01
|
Series: | Scientific Reports |
Online Access: | https://doi.org/10.1038/s41598-017-01464-2 |
id |
doaj-e462d5eb8fbe4b6fb850806b7c61aca1 |
---|---|
record_format |
Article |
spelling |
doaj-e462d5eb8fbe4b6fb850806b7c61aca12020-12-08T00:51:23ZengNature Publishing GroupScientific Reports2045-23222017-05-017111110.1038/s41598-017-01464-2Thermodynamic Scaling of the Dynamics of a Strongly Hydrogen-Bonded Glass-FormerMichela Romanini0María Barrio1Roberto Macovez2María D. Ruiz-Martin3Simone Capaccioli4Josep Ll. Tamarit5Grup de Caracterització de Materials, Universitat Politècnica de Catalunya, EEBE, Departament de Física, and Barcelona Research Center in Multiscale Science and EngineeringGrup de Caracterització de Materials, Universitat Politècnica de Catalunya, EEBE, Departament de Física, and Barcelona Research Center in Multiscale Science and EngineeringGrup de Caracterització de Materials, Universitat Politècnica de Catalunya, EEBE, Departament de Física, and Barcelona Research Center in Multiscale Science and EngineeringGrup de Caracterització de Materials, Universitat Politècnica de Catalunya, EEBE, Departament de Física, and Barcelona Research Center in Multiscale Science and EngineeringDipartimento di Fisica, Università di Pisa, and IPCF-CNRGrup de Caracterització de Materials, Universitat Politècnica de Catalunya, EEBE, Departament de Física, and Barcelona Research Center in Multiscale Science and EngineeringAbstract We probe the temperature- and pressure-dependent specific volume (v) and dipolar dynamics of the amorphous phase (in both the supercooled liquid and glass states) of the ternidazole drug (TDZ). Three molecular dynamic processes are identified by means of dielectric spectroscopy, namely the α relaxation, which vitrifies at the glass transition, a Johari-Goldstein β JG relaxation, and an intramolecular process associated with the relaxation motion of the propanol chain of the TDZ molecule. The lineshapes of dielectric spectra characterized by the same relaxation time (isochronal spectra) are virtually identical, within the studied temperature and pressure ranges, so that the time-temperature-pressure superposition principle holds for TDZ. The α and β JG relaxation times fulfil the density-dependent thermodynamic scaling: master curves result when they are plotted against the thermodynamic quantity Tv γ , with thermodynamic exponent γ approximately equal to 2. These results show that the dynamics of TDZ, a system characterized by strong hydrogen bonding, is characterized by an isomorphism similar to that of van-der-Waals systems. The low value of γ can be rationalized in terms of the relatively weak density-dependence of the dynamics of hydrogen-bonded systems.https://doi.org/10.1038/s41598-017-01464-2 |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Michela Romanini María Barrio Roberto Macovez María D. Ruiz-Martin Simone Capaccioli Josep Ll. Tamarit |
spellingShingle |
Michela Romanini María Barrio Roberto Macovez María D. Ruiz-Martin Simone Capaccioli Josep Ll. Tamarit Thermodynamic Scaling of the Dynamics of a Strongly Hydrogen-Bonded Glass-Former Scientific Reports |
author_facet |
Michela Romanini María Barrio Roberto Macovez María D. Ruiz-Martin Simone Capaccioli Josep Ll. Tamarit |
author_sort |
Michela Romanini |
title |
Thermodynamic Scaling of the Dynamics of a Strongly Hydrogen-Bonded Glass-Former |
title_short |
Thermodynamic Scaling of the Dynamics of a Strongly Hydrogen-Bonded Glass-Former |
title_full |
Thermodynamic Scaling of the Dynamics of a Strongly Hydrogen-Bonded Glass-Former |
title_fullStr |
Thermodynamic Scaling of the Dynamics of a Strongly Hydrogen-Bonded Glass-Former |
title_full_unstemmed |
Thermodynamic Scaling of the Dynamics of a Strongly Hydrogen-Bonded Glass-Former |
title_sort |
thermodynamic scaling of the dynamics of a strongly hydrogen-bonded glass-former |
publisher |
Nature Publishing Group |
series |
Scientific Reports |
issn |
2045-2322 |
publishDate |
2017-05-01 |
description |
Abstract We probe the temperature- and pressure-dependent specific volume (v) and dipolar dynamics of the amorphous phase (in both the supercooled liquid and glass states) of the ternidazole drug (TDZ). Three molecular dynamic processes are identified by means of dielectric spectroscopy, namely the α relaxation, which vitrifies at the glass transition, a Johari-Goldstein β JG relaxation, and an intramolecular process associated with the relaxation motion of the propanol chain of the TDZ molecule. The lineshapes of dielectric spectra characterized by the same relaxation time (isochronal spectra) are virtually identical, within the studied temperature and pressure ranges, so that the time-temperature-pressure superposition principle holds for TDZ. The α and β JG relaxation times fulfil the density-dependent thermodynamic scaling: master curves result when they are plotted against the thermodynamic quantity Tv γ , with thermodynamic exponent γ approximately equal to 2. These results show that the dynamics of TDZ, a system characterized by strong hydrogen bonding, is characterized by an isomorphism similar to that of van-der-Waals systems. The low value of γ can be rationalized in terms of the relatively weak density-dependence of the dynamics of hydrogen-bonded systems. |
url |
https://doi.org/10.1038/s41598-017-01464-2 |
work_keys_str_mv |
AT michelaromanini thermodynamicscalingofthedynamicsofastronglyhydrogenbondedglassformer AT mariabarrio thermodynamicscalingofthedynamicsofastronglyhydrogenbondedglassformer AT robertomacovez thermodynamicscalingofthedynamicsofastronglyhydrogenbondedglassformer AT mariadruizmartin thermodynamicscalingofthedynamicsofastronglyhydrogenbondedglassformer AT simonecapaccioli thermodynamicscalingofthedynamicsofastronglyhydrogenbondedglassformer AT joseplltamarit thermodynamicscalingofthedynamicsofastronglyhydrogenbondedglassformer |
_version_ |
1724395862093725696 |