Binary Phosphate Glasses

From Sato et al. (1992). Both figures used by permission of Elsevier Science. 

One-dimensional - P NMR is only able to probe the the local structure of phosphate glasses. To gain information about the manner in which the different Q units or domains in phosphate glasses are connected, two-dimensional MAS exchange experiments have been used in which radio-frequency dipolar recoupling (RFDR) techniques allow the reintroduction of the through-space dipolar-dipolar interaction even 

The application of P NMR to structural studies of alkali and alkaline earth phosphate and aluminophosphate glasses, fluorophosphate glasses and phosphorus oxynitride glasses has been reviewed by Kirkpatrick and Brow (1995). 

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M.A. Karakassides, A. Saranti, 1. Koutselas, Preparation and structural study of binary phosphate glasses with high calcium and/or magnesium content. J. Non-Cryst. Solids 347(1-3), 69-79 (2004)... 

T.M. Alam, S. Conzone, R.K. Brow, T.J. Boyle, Li, Li nuclear magnetic resonance investigation of lithium coordination in binary phosphate glasses. J. Non-Cryst. Solids 258(1-3), 140-154 (1999)... 

Takahashi, K. Binary Phosphate, Silicophosphate Borophosphate, and Alumiaophosphate Glasses, Their Structure and Properties, p. 366. Proc. 6th International Congress on Glass. Washington, D. C. 1962. 

Both Li and Li MAS NMR has been used to investigate the local Li coordination environment in a series of binary lithium phosphate glasses (Alam et al. 1999). The Li chemical shifts, which approximate closely to the isotropic chemical shifts, increase... 

An analogous approach has been applied to a number of binary and ternary phosphate glasses, resulting in very insightful quahtative and quantitative information [67-77]. First of all, the observation of crosspeaks in 2D-exchange, RFDR, as well as DQ-ejqjeriments unambiguously reveal the occurrence of Q< >-and Unkages. 

P. Losso, B. Schnabel, C. Jager, U. Sternberg, D. Stachel, D.O. Smith, P NMR investigations of binary alkaline earth phosphate glasses of ultra phosphate composition, J. Non-Cryst. Solids 143 (1992) 265-273. 

Analysis, under high resolution, of the SrO emission spectrum yielded the following vibrational wavenumbers SrO 654.4774956 cm SrO 653.8864510 cm and SrO 653.30998 cm . Raman spectroscopy was used to characterise the binary strontium phosphate glasses, xSrO.(100 — x)P20s, where 0.5 > x > 0. There were signihcant differences from the calcium analogues. ... 

B.C. Tischendorf, T.M. Alam, R.T. Cygan, J.U. Otaigbe, The structure and properties of binary zinc phosphate glasses studied by molecular dynamics simulations. J. Non-Cryst. Solids 316(2-3), 261-272 (2003)... 

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