Optical properties of glasses in the Li2O–MoO3–P2O5 system

Abstract

Glasses xLi 2 O-(50-x)(MoO 3 ) 2 -50P 2 O 5 with x= 10, 20, 30, and 40 mol% were prepared and their optical and electrical properties were investigated. Analysis of the IR spectra revealed that the Li + ions act as a glass modifier that enter the glass network by breaking up other linkages and creating non-bridging oxygens in the network. The optical absorption edge of the glasses was measured for specimens in the form of thin blown films and the optical absorption spectra of those were recorded in the range 200-800 nm. From the optical absorption edges studies, the optical band gap (E opt ) and the Urbach energy (E e ) values have been evaluated by following the available semiempirical theories. The linear variation of (αhν) 1/2 with hν, is taken as evidence of indirect interband transitions. The E opt values were found to decrease with increasing Li 2 O content by causing increase in the number of nonbridging oxygens in network. The Urbach tail analysis gives the width of localized states between 0.48 and 0.74 eV.

Optical and Thermal Properties of Mixed Alkali Phosphate Based Glasses

“…Glassy networks with structure of ultraphosphate, composed of one non-bridging and three bridging oxygens. The fundamental feature of ultrphosphate units is a P=O bond at about 1378 cm -1 [12,14,31,35]. However, when P 2 O 5 mixed with other oxides, such as transition metal oxides, some changes occur in position and extent of the bonds [31].…”

“…The fundamental feature of ultrphosphate units is a P=O bond at about 1378 cm -1 [12,14,31,35]. However, when P 2 O 5 mixed with other oxides, such as transition metal oxides, some changes occur in position and extent of the bonds [31]. In glass networks, V 2 O 5 has a dual role, partly acts as a glass modifier and partly as a glass former [14,20].…”

Conductivity studies on microwave synthesized glasses

“…[8][9][10] Further, increase in the concentration of the modifier oxide has been found to have profound effect on transport, physical, chemical and optical properties of glasses. [11][12][13][14][15] It is expected that transition metal oxide doped with alkali-modified glasses exhibit both ionic and electronic (polaronic) conduction. 10,16 Generally, alkali-rich glasses exhibit dominant ion conductivity, while TMI-rich glasses exhibit dominant electronic conductivity.…”

Vidros dopados com íons terras raras para detectores de radiação de alta energia

“…Ao se compreender melhor o processo de formação vítrea, e como a taxa do resfriamento é primordial para a sua configuração estrutural, o que se passou a analisar é como esses "espaços desordenados" dos vidros se relacionam com os elementos terras raras que serão utilizados para a dopagem. Estudos feitos com TR e vidros a base de fluoretos e fosfatos destacam o uso de európio, térbio, cério e itérbio trivalente para aplicações em áreas biológicas, espectroscópicas com foco em estudos científicos, aplicações com foco na área da radiação de alta energia e até mesmo fusão a laser, bem como o uso de cério trivalente para a produção de vidros cintiladores [18][19][20].…”