%0 Journal Article
%T Effect of Stepwise Replacement of Non-Oxide to Oxide Group on Structural Properties of ¡¤LiF¡¤ Glasses
%A Susheel Arora
%A Virender Kundu
%A D. R. Goyal
%A A. S. Maan
%J ISRN Spectroscopy
%D 2012
%R 10.5402/2012/896492
%X Bismuth fluoroborate glasses with compositions xBi2O3¡¤(40 £¿ x)LiF¡¤60 B2O3 (x = 0, 5, 10, 15, and 20) are synthesized by melt-quench method. XRD pattern is obtained for all the samples to confirm their amorphous nature. FTIR spectroscopy is carried out for the reported samples. It reflects the effect of replacement of a non-oxide group (LiF) with an oxide group (Bi2O3) in the glass network, due to the presence of the various absorption bands and their shifting with such replacement, assigning a role of network modifier to Bi2O3. Density and molar volume show an increase in their values with increase in Bi2O3 concentration. Theoretical optical basicity is calculated for the reported samples, which shows a decreasing trend with the increasing concentration of Bi2O3. 1. Introduction B2O3 is one of the best glass formers due to the sheet-like structure of boron-oxygen triangles in borate glasses, with their ability to connect themselves to form a network [1, 2]. A random arrangement of various atomic and molecular species is easily formed in borate glasses which is the basic requirement for glass formation. A number of modifications in the properties of the borate glasses, with the addition of alkali halides, have been reported so far [3¨C9]. The inclusion of LiF in the borate glass network brings out some structural changes [3], which in turn become responsible for the change in various properties. Some new units like BO2F, BO2F2, BOF3, and BO3F are formed by the replacement of few oxygen atoms by fluorine ions [4¨C6]. Also, there may be an increase in the number of polyhedral groups of boron and oxygen, which in turn increases the number of nonbridging oxygen atoms [7¨C9]. Bi2O3 possesses high third-order nonlinear optical susceptibility caused by high density and refractive index [10, 11]. This property makes it to have numerous nonlinearity applications such as optical switching [12, 13], supercontinuum generation [14], and wavelength conversion [15]. Luminescent materials have always been studied by researchers for their wide range of applications. Noto reported the luminescence spectroscopy of some systems containing rare earth ions [16, 17]. Also, bismuth ion acts as an efficient luminescent activator with applications in lasers as a sensitizer for some rare earth ions [18, 19]. The purpose of this paper is to report the change in structural and physical properties of glasses with the stepwise replacement of LiF by Bi2O3. The addition of provides an opportunity for the new molecular units to be formed with more numbers of NBOs. 2. Experimental Details
%U http://www.hindawi.com/journals/isrn.spectroscopy/2012/896492/