title: Effects of the substitution of P2O5 by B2O3 on the structure and dielectric properties in (90-x) P2O5-xB2O3-10Fe2O3 glasses.
abstract: 90%[xB2O3 (1-x) P2O5] 10%Fe2O3, glass systems where (x=0 mol%, 5 mol%, 10 mol%, 15 mol%, 20 mol%) was prepared via a melt quenching technique. The structure of glass is investigated at room temperature by, Raman and EPR spectroscopy. Raman studies have been performed on these glasses to examine the distribution of different borate and phosphate structural groups. We have noted an increase from 3 to 4 in the coordination number of the boron atoms from 3 to 4, i.e., the conversion of the BO3 triangular structural units into BO4 tetrahedra. The samples have been investigated by means of electron paramagnetic resonance (EPR). The results obtained from the gef=4.28 EPR line are typical of the occurrence of iron (III) occupying substitutional sites. Moreover, the dielectric sizes such as ε'(ω), ε″(ω), imaginary parts of the electrical modulus, M(*)(ω) and the loss tanδ, their variation with frequency at room temperature show a decrease in relaxation intensity with an increase in the concentration of (B2O3). On the present work, we have found a weak extinction index with our new glass.
authors.affiliation: Unité de recherche, Matériaux nouveaux et dispositifs électroniques organiques Faculté des sciences de Monastir, Université de Monastir, Avenue de l'environnement, 5019 Monastir, Tunisia. Electronic address: sdirinasr@yahoo.fr.
authors.forename: N
authors.initials: N
authors.lastname: Sdiri
authors.forename: H
authors.initials: H
authors.lastname: Elhouichet
authors.forename: H
authors.initials: H
authors.lastname: Dhaou
authors.forename: F
authors.initials: F
authors.lastname: Mokhtar
mesh_terms: D001896:Boron Compounds / Q000737:chemistry*; D017097:Electric Impedance; D004578:Electron Spin Resonance Spectroscopy; D005290:Ferric Compounds / Q000737:chemistry*; D005898:Glass / Q000737:chemistry*; D017553:Phosphorus Compounds / Q000737:chemistry*; D013059:Spectrum Analysis, Raman
chemical_list: D001896:Boron Compounds; D005290:Ferric Compounds; D017553:Phosphorus Compounds; C000499:ferric oxide; C042168:boron oxide; C012500:phosphorus pentoxide
keywords: EPR spectroscopy; Glasses; Raman; Relaxations