Effect of the mode formation on the structure of amorphous materials in the TiO2-PbO system

Glass formation in the MoO3–CuO–PbO system

“…For the samples rich in PbO (70-80 mol%) we can suppose that the main units forming the network of glasses are PbO n (n = 3,4) polyhedra, forming chains, between which there are isolated MoO 4 groups (band at 800-790 cm À1 ). Such a chain structure was also proposed for other compositions of glasses rich in PbO [25,26]. Moreover the same chains structure is also characteristic for crystal PbO and PbMoO 4 [27] detected near the boundary of glass formation (see Fig.…”

Dielectric dispersion and spectroscopic investigations on Na2SO4–B2O3–P2O5 glasses mixed with low concentrations of TiO2

“…The spectra have also exhibited three usual bands originated from borate groups in the regions 1381-1414 cm −1 due to BO 3 units, 944-964 cm −1 due to BO 4 units and 709-724 cm −1 due to bending vibrations of B O B linkages [22]. In the spectral regions 658-678 cm −1 and 1124-1148 cm −1 vibrational bands corresponding to bending and asymmetric modes of SO 4 2− groups, respectively are also observed [23,24]; additionally a prominent band in the regions 581-620 cm −1 attributed to the vibrations of TiO 6 structural units [25][26][27] is also located in these spectra. With the gradual introduction of TiO 2 in the glass network, all the asymmetrical bands are observed to grow at the expense of symmetrical bands.…”

Induced crystallization and physical properties of Li2O–CaF2–P2O5:TiO2 glass system

“…Earlier reports on some other glass systems containing TiO 2 suggested that upon heating at about 700 • C, there is a possibility for the reduction of Ti 4+ ions to Ti 3+ ions [11]. Further, the reduction, Ti 4+ + e = Ti 3+ , takes place only with E 0 = 0.2 V. The Ti 4+ ions [23][24][25][26][27][28]. The TiO 6 octahedrons may be viewed as entwined with PO 4 structural units forming TiPO 9 where all the oxygens are bridging (Fig.…”

“…In the IR spectrum of the sample T 2 , two additional prominent bands were also observed at 740 and 652 cm −1 . Further, it was also established that in the IR spectra of glasses and their crystalline products, the bands due to TiO 6 units lie around 650 cm −1 , whereas the bands due to TiO 4 units lie in the high frequency region [23][24][25][26][27][28]. Based up on the literature survey, the first band is identified due to Ti-O-Ti symmetric stretching vibrations of TiO 4 units.…”