Optical, physical and structural studies of vanadium doped P2O5–BaO–Li2O glasses

Abstract

a b s t r a c tGlasses in the compositions (Li 2 O) 25 -(BaO) 25 -(P 2 O 5 ) 50 À x -(V 2 O 5 ) x (with x ¼0.5,1.0,1.5,2.0,2.5, and 3.0 mol %) have been prepared by the conventional melt quenching technique. X-ray powder diffractrogram show broad peaks which conforms glassy nature of the sample. Differential scanning calorimetry (DSC) thermograms show characteristic glass transition temperature (T g ) and it increases with increasing substitution of V 2 O 5 for P 2 O 5 . The measured physical parameters like density, refractive index, ionic concentration and electronic polarizability are found to vary linearly with increasing x. Infrared spectra exhibits few bands, which are attributed to (P ¼O) AS , (P¼ O) S , (V¼O), (P-O-P) AS ,P-O-V, (P-O-P) AS and O-P-O vibrations. The optical absorption spectra of VO 2 þ ions in these glasses show three bands and are assigned to the 2 B 2 -2 E, 2 B 2 -2 B 1 and 2 B 2 -2 A 1 transitions. Electron paramagnetic resonance spectra of all the glass samples exhibit resonance signals characteristic of VO 2 þ ions. The values of SpinHamiltonian parameters indicate that the VO 2 þ ions are present in octahedral sites with tetragonal compression and belong to C 4V symmetry.

The Gladstone–Dale relation: Applications in oxide glasses

“…For the relation to hold value, the experimental and calculated values should be nearly identical and form a linear trend with a slope of 1. From Figure 1, it is seen that the previous assessment that the Gladstone–Dale relation holds reasonably well for silicate glasses is a valid assumption 36–63 . For the purpose of this discussion, measurements done at 589 and 589.3 nm were considered sodium D line values.…”

“…Comparison of experimental index‐of‐refraction values measured at the sodium D line compared to calculated values for different glass families. Adapted from data obtained from Ref 36–63…”

“…Therefore, it can be generally expected that the difference between the experimental index of refraction and the one calculated by the Gladstone–Dale relation should decrease with increasing wavelength. Unfortunately, this is not always the case, as seen in the top plot of Figure 3, which shows the average percentage error between the calculated index of refraction and experimentally measured one 34,36–63,72–112 . The overall average percentage error value in n was determined by averaging the percentage error of all glasses measured at a specific wavelength, while the average percentage error in n for each glass family was determined using only glasses in that family.…”

Observation of structural, spectral characterizations and correlation of physical parameters on VO²⁺ ions doped Cadmium Lithium Sodium Borate glasses

“…Usually if β1 2 = 1 the bond should be purely ionic, if β1 2 = 0.5 the bond should be covalent. In this exertion the evaluated values of β1 2 and επ 2 implied the in plane σ-bonding and out of plane π -bonding are covalent or moderately covalent and β 2 2 is assumed to be 1 for the in-plane π-bonding with the equilateral field ligands [38]. κ is Fermi interaction parameter which is a unit less and dimension less invariable, portrayed core s polarization corresponding single electron density of vanadium nucleus and P is a dipolar coupling constant determine radial distribution of single electron wave function.…”

Theoretical studies of the concentration dependences of d–d transition band, g factors, and local distortion for V4+ in Li2O–PbO–B2O3–P2O5 glasses

“…[13] Owing to their abundant nd (n = 3-5) energy levels sensitive to delicate environmental variations, transition-metal ions are essential ingredients playing a core role in modifying optical and electrical properties and useful optical and paramagnetic probes for the local structures of the host glasses. In particular, various studies reveal strong concentration dependences of both local structures and resultant performances of glass systems on transition-metal dopants, [14][15][16][17][18][19][20] which would enrich the modulation methods for the performance enhancement of these glasses. Take the V 2 O 5 -doped glasses as an example.…”