Raman spectroscopy of calcium phosphate glasses with varying CaO modifier concentrations

Journal Article · · Chemistry of Materials; (United States)

OSTI ID:5202235

Pemberton, J E; Latifzadeh, L; Fletcher, J P; Risbud, S H ^[1]

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1. Univ. of Arizona, Tucson (USA)

Raman spectroscopy has been performed on a series of calcium phosphate glasses prepared from calcium dihydrogenphosphate and CaO in which the CaO content is varied from that of the metaphosphate stoichiometry, in which the mole ratio of CaO to P{sub 2}O{sub 5} is 1.00, to a stoichiometry in which the mole ratio is 1.49. Investigation of the vibrational behavior provides insight into the effects of the CaO modifier on the depolymerization processes occurring in these phosphate glasses. Curve-fitting procedures are used to accurately identify peak positions and resolve overlapped bands in the spectra. Depolymerization of the phosphate chains is clearly observed in the vibrational spectra as indicated by shifts in the v{sub s}(POP), r{sub s}(PO{sub 2}), and v{sub as}(PO{sub 2}) vibrations. At the largest CaO modifier concentrations, distinct crystalline phases of {alpha}- and {gamma}-Ca{sub 2}P{sub 2}O{sub 7} are observed. Analysis of the Raman spectra for these systems suggests that crystallization occurs from the short chain regions of the glass.

• OSTI ID: 5202235
• Journal Information: Chemistry of Materials; (United States), Journal Name: Chemistry of Materials; (United States) Vol. 3:1; ISSN CMATE; ISSN 0897-4756
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602 -- Other Materials-- Structure & Phase Studies
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102* -- Chemical & Spectral Procedures
ALKALINE EARTH METAL COMPOUNDS
CALCIUM COMPOUNDS
CALCIUM PHOSPHATES
DATA
EXPERIMENTAL DATA
GLASS
INFORMATION
LASER SPECTROSCOPY
MEASURING METHODS
NUMERICAL DATA
OXYGEN COMPOUNDS
PHOSPHATE GLASS
PHOSPHATES
PHOSPHORUS COMPOUNDS
RAMAN SPECTROSCOPY
SPECTROSCOPY
STOICHIOMETRY