Raman spectroscopic study of the uranyl carbonate mineral voglite

Raman spectroscopy, complemented with infrared spectroscopy, was used to study the uranyl carbonate mineral voglite. The mineral has the formula Ca2Cu2+ [(UO2)(CO3)(3)](CO3)(center dot)6H(2)O, and bands attributed to these vibrating units are readily identified in the Raman spectrum. Symmetric stretching modes at 836 and 1094 cm(-1) are assigned to nu(1)(UO2)(2+) and nu(1)(CO3)(2-) units, respectively. The nu(3) antisymmetric stretching modes of (UO2)(2+) are not observed in the Raman spectrum but may be readily observed in the infrared spectrum at 898 cm(-1). The nu(3) antisymmetric stretching mode of (CO3)(2-) is observed in the Raman spectrum at 1369 cm(-1) as a low intensity band as is also the nu(3)(CO3)(2-) infrared modes at 1362, 1425, 1509 and 1566 cm(-1). No nu(2)(CO3)(2-) Raman bending modes are observed for voglite. The Raman band at 749 cm(-1) and the two infrared bands at 747 and 709 cm(-1) are assigned to the nu(4)(CO3)(2-) bending modes. U-O bond and O-H center dot center dot center dot O bond lengths in the structure of voglite were inferred from the infrared and Raman spectra. Copyright (C) 2007 John Wiley & Sons, Ltd.