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Structural relaxation and quasi-elastic light scattering in glass: approach by ferroelectric and ion-conducting phases.

ABSTRACT: Inelastic light scattering has been utilized for examining the structure of glass and its relaxation. However, the quasi-elastic-light-scattering (QLS) phenomenon has not been addressed in much detail. In this study, we observed pronounced QLS-intensity variations in two temperature domains-supercooled liquid (SCL) state (?-relaxation regime) and below the glass-transition temperature (?-relaxation regime)-in niobium-oxide (Nb(2)O(5))-rich glass. These variations may be interpreted on the basis of the concept of ferroelectric and ion-conducting phases. It was suggested that the observed QLS originates as a result of the polarization fluctuation of NbO(6) units, which is due to the dynamics of the nanometric phase separation in the SCL phase (?-regime), and the fluctuation due to the migration/hopping of conductible ions that are localized in the vicinity of the NbO(6) units (?-regime).

SUBMITTER: Takahashi Y

PROVIDER: S-EPMC3465810 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Structural relaxation and quasi-elastic light scattering in glass: approach by ferroelectric and ion-conducting phases.

Takahashi Yoshihiro Y Nakamura Kensaku K Osada Minoru M Fujiwara Takumi T

Scientific reports 20121008

Inelastic light scattering has been utilized for examining the structure of glass and its relaxation. However, the quasi-elastic-light-scattering (QLS) phenomenon has not been addressed in much detail. In this study, we observed pronounced QLS-intensity variations in two temperature domains-supercooled liquid (SCL) state (α-relaxation regime) and below the glass-transition temperature (β-relaxation regime)-in niobium-oxide (Nb(2)O(5))-rich glass. These variations may be interpreted on the basis ...[more]

PMID: 23056906

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