An ultrasonic study of the loss characteristics and sound velocity was carried out in AgI-Ag2O-B2O3 glasses as a function of temperature and silver-compound concentration. From the behavior of the sound velocity in (Ag2O)y(B2O3)1-y, the formation of fourfold-coordinated boron ions is suggested. This increases rapidly, as a function of y, until y≃0.25; for larger y, a strong production of singly bonded oxygen ions (nonbridging oxygen ions) prevails, which weakens the glassy network. From the analysis of the attenuation peaks in terms of a relaxation-time Gaussian-type distribution, arising from the thermally activated relaxation of mobile silver ions, it is argued that there exists a similarity between the ion motion in a stress field and in an electric one. By way of this analogy and by combining the ultrasonic results with the dc conductivity data in (AgI)x[(Ag2O)y(B2O3)1-y]1-x, the ion-jump distances are calculated. The behavior with AgI concentration is consistent with the structural hypothesis of the existence of silver ions differently bonded and mobile in the glassy matrix.

Acoustic properties and diffusion in superionic glasses

CARINI, Giuseppe;CUTRONI, Maria;FEDERICO, Mauro;GALLI, Giovanni;TRIPODO, Gaspare
1984-01-01

Abstract

An ultrasonic study of the loss characteristics and sound velocity was carried out in AgI-Ag2O-B2O3 glasses as a function of temperature and silver-compound concentration. From the behavior of the sound velocity in (Ag2O)y(B2O3)1-y, the formation of fourfold-coordinated boron ions is suggested. This increases rapidly, as a function of y, until y≃0.25; for larger y, a strong production of singly bonded oxygen ions (nonbridging oxygen ions) prevails, which weakens the glassy network. From the analysis of the attenuation peaks in terms of a relaxation-time Gaussian-type distribution, arising from the thermally activated relaxation of mobile silver ions, it is argued that there exists a similarity between the ion motion in a stress field and in an electric one. By way of this analogy and by combining the ultrasonic results with the dc conductivity data in (AgI)x[(Ag2O)y(B2O3)1-y]1-x, the ion-jump distances are calculated. The behavior with AgI concentration is consistent with the structural hypothesis of the existence of silver ions differently bonded and mobile in the glassy matrix.
1984
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11570/2087828
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact