FTIR reinvestigation of the spectra of synthetic brushite and its partially deuterated analogues

The Fourier transform infrared spectra of brushite, CaHPO4. 2H(2)O and of a series of its partially deuterated analogues were recorded at room tempera ture and at the boiling temperature of liquid nitrogen. The availability of the spectra of deuterated analogues and the instrumental capabilities supe rior to those previously [1-4] employed, made it possible to clarify some o f the questionable points. For example, it is proven that the group of band s at the highest frequencies originate from vibrations of the weakly hydrog en bonded molecules, whereas those in the 3300-3100 cm(-1) region must be t he corresponding vibrations of the water molecules involved in the formatio n of stronger hydrogen bonds. (C) 1999 Elsevier Science B.V. All rights res erved.