Homogeneous Ag2O–2P2O5–CaO–GeO2 glass formation, structural and in vitro studies

Structure and properties of gadolinium loaded calcium phosphate glasses

“…The first one is attributed to the symmetric stretching vibrations of PAOAP bonds in Q 2 metaphosphate units [30,35]. The second one correspond to the symmetric stretching vibrations of OAPAO non-bridging oxygens ((PO 2 ) À groups) in Q 2 phosphate tetrahedra [31,[36][37][38]. Moreover, the Raman spectrum of studied glasses presents seven weak bands centered at 600 cm À1 (assigned to the symmetric stretching vibrations of PAOA terminal bonds), $760 cm À1 (ascribed to the symmetric stretching vibrations of PAOAP associated with Q 1 tetrahedra units), $790 cm À1 (attributed to the symmetric stretching vibrations of PAOAP rings in Q 2 tetrahedra units), $890 cm À1 (correspond to the vibrations of the isolated (PO 4 ) 3À units), $1050 cm À1 (attributed to the symmetric stretching vibrations of (PO 3 ) 2À terminal group from the Q 1 units), $1262 cm À1 (assigned to the asymmetric stretching vibrations of (PO 2 ) À groups in Q 2 units) [35,38,39].…”

Structural and in vitro characterization of TiO2-CaO-P2O5 bioglasses

“…4) presents two strong bands centered at~700 cm − 1 and 1162 cm − 1 assigned as follows: the first one to the symmetric stretching of P-O-P linkages in Q 2 and Q 1 structural units [29,34] and the second one to the symmetric and asymmetric stretching vibration of PO 2 groups (Q 2 structural units) [15,34,35]. At the same time, the Raman spectrum of the glass matrix presents four weak bands centered at~340 cm − 1 (assigned to bending vibration of O-P-O linkages),~550 cm − 1 (assigned to symmetric bending vibration of P-O-terminal bonds),~1025 cm − 1 (ascribed to the symmetric stretching vibration of − PO 3 2 − terminal group groups from the Q 1 species) and~1265 cm − 1 (ascribed to asymmetric stretching vibration of PO 2 groups in Q 2 units) [15,34,36].…”

“…8a) show an increase of absorption bands intensity, and the shift of some bands to lower wavenumber (815 910 cm − 1 , 1115 1110 cm − 1 ). The shift of the absorption band positions is due to changes in the force constants of stretching vibration of P-O − bonds [28,35] which are primarily determined by two parameters: the cation-oxygen force constant F M-O and PO 2 bond angles. Increasing F M-O and decreasing PO 2 angles lead to higher frequency vibrations.…”

One step fabrication of glass–silver@core–shell fibers: silver-doped phosphate glasses as precursors of SERS substrates

“…Additionally, silver and germanium ions enable bioactivity for phosphate-based glasses. 2 Applications of phosphate glasses in solid state ionic conductors, optical data transmission and hermetic seals are also reported in the literature. 1,3 Many transition-metals, alkali-, alkaline-and rare earth oxides form glasses when melted with P 2 O 5 or other phosphate-based substances (e.g.NaH 2 PO 4 $H 2 O).…”