Hysteresis in the temperature dependence of the IR bending vibration of deeply cooled confined water.
J Chem Phys
; 150(22): 224509, 2019 Jun 14.
Article
em En
| MEDLINE
| ID: mdl-31202227
ABSTRACT
Using Fourier Transform Infrared (FTIR) spectroscopy, we investigate the temperature dependence of the bending vibrations of water confined in the pores of a silica hydrogel in the temperature interval of 270-180 K. We also investigate the presence of thermal hysteresis by cooling and reheating temperature scans. The results clearly show the presence, at about 230 K, of a crossover in the temperature dependence of the IR spectra; moreover, the presence of hysteresis is clearly demonstrated. By comparing FTIR data with neutron diffraction data and previous calorimetric data on the same samples, we conclude that the crossover and the hysteretical behavior do not involve a water glass transition or crystallization but are related to a first-order-like liquid-liquid transition.
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01-internacional
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MEDLINE
Idioma:
En
Revista:
J Chem Phys
Ano de publicação:
2019
Tipo de documento:
Article