A Raman spectroscopic study of synthetic giniite
(2007) A Raman spectroscopic study of synthetic giniite. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 66(1):pp. 42-47.
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Abstract
The mineral giniite has been synthesised and characterised by XRD, SEM and Raman and infrared spectroscopy. SEM images of the olive green giniite display a very unusual image of pseudo-spheres with roughened surfaces of around 1 to 10 microns in size. The face to face contact of the spheres suggests that the spheres are colloidal and carry a surface charge. Raman spectroscopy proves the (PO4)3- units are reduced in symmetry and in all probability more than one type of phosphate unit is found in the structure. Raman bands at 77 K are observed at 3380 and 3186 cm-1 with an additional sharp band at 3100 cm-1. The first two bands are assigned to water stretching vibrations and the latter to an OH stretching band. Intense Raman bands observed at 396, 346 and 234 cm-1are attributed to the FeO stretching vibrations. The giniite phosphate units are characterised by two Raman bands at 1023 and 948 cm-1 assigned to symmetric stretching mode of the (PO4)3- units. A complex band is observed at 460.5 cm-1 with additional components at 486.8 and 445.7 cm-1 attributed to the ν2 bending modes suggesting a reduction of symmetry of the (PO4)3- units.
| Item Type: | Journal Article |
|---|---|
| Status: | Published |
| Keywords: | giniite; synthesis; phosphate; kintoreite; segnitite; scanning electron microscopy; Raman spectroscopy |
| Subjects: | Subjects UNSPECIFIED |
| ID Code: | 5741 |
| Deposited By: | Frost, Ray |
| Deposited On: | 12 March 2007 |
| Alternative Locations: | http://dx.doi.org/10.1016/j.saa.2006.02.018 |
| Copyright Owner: | Copyright 2007 Elsevier |
| Copyright Statement: | Reproduced in accordance with the copyright policy of the publisher. |