Published March 1979 | Version v1
Journal article

Atomic Center interactions in BaO; Al2O3; B2O3 glasses containing silver

  • 1. Sao Paulo Univ. (Brazil). Inst. de Fisica

Description

The EPR study of borate glasses, with 30% of BaO and 5% mole of silver, X-irradiated at 770K, showed Ag0 and Ag++ centers. In addition were detected the boron electron center (BEC) and the boron hole center. The silver centers and BEC were studied in detail and the spin Hamiltonian parameters are given. The different Al2O3 concentrations exerted only little influence on the tabulated constants. The Ag+2 center was not observed, indicating that the collisions between Ag atoms are not very frequent in these glasses, even during the process of thermal bleaching. The hfs of the boron electron center suffered severe variation as one compared the spectra of base glasses and those containing silver. This is an evidence of the action of silver as a glass modifier like the alkali atoms

Abstract (Portuguese)

O estudo de EPR dos vidros com boratos, contendo 30% de BaO e 5% mol de prata, irradiados com raios X a 770K, revelou a presenca dos centros Ag0 e Ag++. Foram tambem observados o centro do eletron do boro (BEC) e o centro de buraco do boro. Os centros de prata e o BEC foram estudados em detalhe, sendo obtidos os parametros de Hamiltoniana de spin. As diferentes concentracoes de Al2O3 exerceram apenas uma pequena influencia sobre as constantes expressas nas Tabelas. O centro de Ag+2 nao foi observado, indicando que as colisoes entre os atomos de Ag nao sao muito frequentes nestes vidros, mesmo durante o processo de decaimento termico. A constante de interacao hiperfina do centro de eletron do boro sofreu acentuada variacao quando da comparacao dos espectros dos vidros-base com os que contem prata. Este fato torna evidente a atuacao da prata como modificadora do vidro, a semelhanca dos atomos alcalinos

Additional details

Publishing Information

Journal Title
Rev. Bras. Fis.
Journal Volume
9
Journal Issue
1
Series
Rev. Bras. Fis.
Journal Page Range
93-107
ISSN
0374-4922