A vibrational spectroscopic study of the phosphate mineral vantasselite Al4(PO4)3(OH)3 9H2O.

Abstract
We have studied the phosphate mineral vantasselite Al4(PO4)3(OH)3 9H2O using a combination of SEM with EDX and Raman and infrared spectroscopy. Qualitative chemical analysis shows Al, Fe and P. Raman bands at 1013 and 1027 cm 1 are assigned to the PO43 m1 symmetric stretching mode. The observation of two bands suggests the non-equivalence of the phosphate units in the vantasselite structure. Raman bands at 1051, 1076 and 1090 cm 1 are attributed to the PO43 m3 antisymmetric stretching vibration. A comparison is made with the spectroscopy of wardite. Strong infrared bands at 1044, 1078, 1092, 1112, 1133, 1180 and 1210 cm 1 are attributed to the PO4 3 m3 antisymmetric stretching mode. Some of these bands may be due to dAl2OH deformation modes. Vibrational spectroscopy offers a mechanism for the study of the molecular structure of vantasselite.
Description
Keywords
Vantasselite, Phosphate, Raman spectroscopy, Infrared spectroscopy
Citation
FROST, R, L. et al. A vibrational spectroscopic study of the phosphate mineral vantasselite Al4(PO4)3(OH)3 9H2O. Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy, v. 147, p. 185-192, 2015. Disponível em: <http://www.sciencedirect.com/science/article/pii/S1386142515004059>. Acesso em: 08 set. 2015.