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Abstract Glass materials of composition CaO–Y 2 O 3 –B 2 O 3 –P 2 O 5 added with different concentrations of NiO (Ni2+:CYBP) are synthesized by conventional rapid melt quenching method. Various physical properties of these glasses such as polaron radius (r p), molar volume (V m), optical basicity (Λ th) and refractive index (μ) are studied. As an elastic characterization Young's modulus (Y), Poison ratio (σ) and micro hardness (H) of these glasses are studied. These grades suggest that the prepared materials are mechanically hard and exhibiting covalently interlinked structure. Further these samples are characterized by various techniques such as differential thermal analysis, thermoluminiscence, optical absorption, photoluminescence, Ionic conductivity and dielectric dispersion. The thermoluminiscence grades such as peak temperature maximum (T m), shape symmetry factor (μ sf) and activation energies (E τ , E δ and E ω) are studied at various UV irradiation levels. These results strongly recommended that the both electron and hole trap centers were created at the deeper trap levels and contribute higher orders of thermoluminiscence emission with in these glasses subjected to higher orders of temperature and UV irradiation. The various optical absorption and photoluminescence factor's such as, optical band gap (E o), nephelauxetic ratio (β), emission cross section (Ω), branching ratio (ξ) and radiative life times (τ) are studied. These grades found to be maximum for the material which has 0.5 mol% of NiO concentration may be most suggestible for optoelectronic application. The dc and ac conductivity (σ dc & σ ac) of these glasses are estimated. The various dielectric parameter's such as loss tangent (Tan (ϕ)), temperature region of relaxation (ΔT), density of states near Fermi level (N(E f)), activation energies of both dipoles and conduction (E d and E c) are also calculated. These reports clearly disclose that the octahedrally located Ni2+ ions are increasing with increase NiO concentration with in present calcio yttria borophosphate glasses. [ABSTRACT FROM AUTHOR]

• The Ba (10-x) Mn x La 30 Si 60 glasses are capable of radiation shielding. • The microhardness (10.784 ∼ GPa) range, suggest higher rigidity and elastic strength. • The glass with 1.0 mol% of MnO concentration is showing better TL intensities. • The super-exchange dipole-dipole interaction and rhombic distortion with in the glasses lead to electron paramagnetic resonance. • Glasses are EPR-TL correlative upon suitable gamma irradiation. The well-known phenomenon, electron paramagnetic resonance, and thermoluminescence are used to investigate paramagnetically, and thermo-luminescent behavior of the materials to advance magneto-thermo-lumina applications. However, still, there is a necessity to introduce a correlation (or) mechanism in between electron paramagnetic resonance, and thermoluminescence to understand the radiation shielding (or) electromagnetic induction shielding phenomenon within the resource like glasses, ceramics, thin film (or) polymers. In this view, the Ba (10-x) Mn x La 30 Si 60 series of glasses are prepared. The non-crystallinity behavior and glass-forming abilities are verified by X-ray diffraction and differential thermal analysis characterization techniques. The glasses are showing non-homogeneity, de-polymerization, entropic, and de-clustering behavior with increased MnO concentration. The thermal stabilities of the glasses are reported from the DTA studies. Ultrasonic velocities were recorded to evaluate the elastic characteristics of glasses. The radiation shielding studies of glasses suggest the radiation shielding phenomenon purely a function of the MnO concentration. In this view, the results and values of mass attenuation coefficient, radiation protection efficiency, mean free path, and energy absorption build-up factor suggest more glassy thickness is required to attenuate high energy radiation. The electron paramagnetic resonance reports suggest high order of dipole-dipole super exchange interaction and rhombohedral distortion within the glasses. Which also reveals the six-state characteristic trace of the octahedral Mn2+ ions. Upon 50 kGy, γ-irradiation, the thermoluminescence properties of the glasses are reported. Trap depth parameters are calculated, which reveal the resource developed are thermoluminescent at low activation energies. Moreover, to introduce the detailed correlation between electron paramagnetic resonance, and thermoluminescence phenomenon, we have annealed the glasses under 0 to 300°C temperature and upon the 0 to 50 kGy γ - irradiation dose level. In this view, the results upon the electron paramagnetic resonance and thermoluminescence properties obtained for the glasses are highly correlative. [ABSTRACT FROM AUTHOR]

• The observed difference in glass crystallization to glass transition temperature from DTA spectra of the existing glass resources suggest that the decrease in devitrification up to 0.4 mol% of CoO concentration. There after the materials prepared were following quite reverse trend with further increase of CoO concentration. • The evaluations of both elastic module's, micro hardness & thermal stability of existing glasses are quite better than the evaluations of classical borate (or) borophosphate glasses might be more useful. • UV irradiated thermoluminiscence of present glasses are reported. All observed TL measurements suggest that the sample of 0.4 mol% of CoO concentration ( δ 4) exhibiting good shape symmetry factor (u) and low AE's (E τ , E δ & E ω) under 15 min of UV irradiation might be good TL asset. • The optical evaluations such as crystal field stabilization energy (D q), racah (B & C) and nephelauxetic ratio (β 0) parameters are projected. The variation in these parameters with increase in CoO content lead to decrease in optical band gap (E o) evaluations, which are found to be least for the glass sample of 0.4 mol% CoO concentration might be good optical asset to develop novel class of laser active mediums. • The radiative out comes of emissive cross section and transition probability of the peaks corresponding to the transitions 2T 1g (H) → 4T 1g (F) & 4T 1 (4P) → 4A 2 (4F) are exhibited best for the glass prepared with 0.4 mol% of CoO concentration might be most useful as radiative resource. The glasses of composition (25-x) LiF–05 Bi 2 O 3 –15 P 2 O–55 SiO 2 : x CoO have prepared (where 'x' is ranging from 0 to 0.5 mol% in step size of 0.1). Prepared samples are characterized by both structural and optical techniques. The results drawn from structural reports suggest that the samples prepared were exhibiting covalently associated interlinked structure. Thermal stability findings from differential thermal analysis disclose that the samples prepared are glassy in nature. X-Ray diffraction reports strongly acclaim the differential thermal analysis conclusions back too. Thermoluminiscence measurements suggest that the sample of 0.4 mol% of CoO concentration exhibiting good shape symmetry factor and low activation energy (~ 0.65) under 15 min of UV - irradiation might be good thermoluminiscence asset. The optical evaluations such as Racah parameters, crystal field stabilization energy and nephelauxetic ratio are additionally projected. The variation in these evaluations with increase in CoO concentration further lead to decrease in optical band gap (~ 2.31 eV) evaluations, which are found to be least for the glass models of 0.4 mol% CoO concentration might be good optical asset to develop novel class of laser active mediums. The radiative evolutions of both emission cross section and transitions probability corresponding to the emissive peaks 2T 1g (H) →4T 1g (F) &4T 1 (4P) →4A 2 (4F) assessed by Photoluminescence technique. All the results drawn from radiative studies are due to octahedrally co-ordinated Co2+ ions and also found to be best for the sample of 0.4 mol% CoO concentration might be useful luminescent resource. [ABSTRACT FROM AUTHOR]

In this study, we obtained nickel oxide-doped CaAl 2 SiO 6 glasses and analyzed their structural, optical, thermoluminescent, and photoluminescent properties. In general, NiO-doped glasses are useful as optical materials. However, optical materials such as glasses containing Ni2+ ions require refinement of their properties in terms of their structure, thermal stability, microhardness, electrical conductivity, and luminescence to facilitate the development of advanced thermoluminescent materials. Thus, Ni2+ ionic CaAl 2 SiO 6 glasses were synthesized and tested in this study. We observed the amorphous behavior of samples by X-ray diffraction, scanning electron microscopy, differential thermal analysis, and Fourier transform-infrared (FT-IR) spectroscopy. The order of density, oxygen packing density, polaronic radius, molar volume, and refractive index were evaluated for the glasses. The glass transition temperatures were identified using DTA to assess the order of the thermal stabilities, where the highest was found for the Ni 0.6 Ca 9.4 Al 30 Si 60 glass. The modes of molecular vibrations for Ni–O–Ni, Ca–O–Ca, Al–O–Al, and Si–O–Si molecules were identified using FT-IR. The highest transmittance intensities were determined for the Ni 0.6 Ca 9.4 Al 30 Si 60 glass. The order of the electrical conductivity and activation energy were obtained for glasses using DC conductivity measurements, where the highest was found for the Ni 0.6 Ca 9.4 Al 30 Si 60 glass. Optical absorption spectra were recorded for the glasses to determine the order of the band gap (∼0.78 eV) and nephelauxetic ratio (0.799). The photoluminescence was recorded for the glasses at an excitation wavelength of 400 nm to determine the order of the transition probability (∼1.85 S–1) and luminescence emission cross section (∼0.819 × 10−34 cm2). The highest transmittance intensities were obtained for the Ni 0.6 Ca 9.4 Al 30 Si 60 glass. Thermoluminescence was recorded for the glasses under gamma irradiation at a dose of 30 kGy, which yielded the shape symmetry factor (∼0.535%), frequency factor (1.31 S–1), and activation energy (∼0.551 eV). Irradiative thermoluminescent analysis suggested a higher order octahedral tendency, and the divalent oxidation states for nickel ions in the glass with an NiO concentration of 0.6 mol% obtained the best thermoluminescent intensities. The orders of the elastic modulus, nephelauxetic ratio, and microhardness for the glasses suggested covalently connected elastic lattices. • Microhardness range of the glasses, reveal the elastic strength. Which is found to be high in comparison with borophosphate glasses. • The d. c. Conductivity range of glasses suggest higher orders of polaronic radius, interstitial defects, and the octahedral tendency of Ni2+ ions, with in the glasses. • The order of ionic radius, trap centers, and the octahedral tendency of Ni2+ ions, with in the glasses suggest glasses will be useful advanced TL resource. The shape symmetry factor and low A.E.'s of the glasses under thermoluminescence studies suggest materials are TL active for low energies. • The order of the optical bandgap, transition probability and cross-section of the glasses are a highly suggestible for photonic resource. Due to the high orders of refractive index, the octahedral tendency of Ni2+ ions, and nephelauxetic ratio, the Ni-0.6 glass exhibited best spectroscopic properties in comparison. [ABSTRACT FROM AUTHOR]