Vibrational spectroscopic study of the uranyl selenite mineral derriksite Cu4UO2(SeO3)2(OH)6-H2O.

Abstract

Raman spectrum of the mineral derriksite Cu4UO2(SeO3)2(OH)6_H2O was studied and complemented by the infrared spectrum of this mineral. Both spectra were interpreted and partly compared with the spectra of demesmaekerite, marthozite, larisaite, haynesite and piretite. Observed Raman and infrared bands were attributed to the (UO2)2+, (SeO3)2_, (OH)_ and H2O vibrations. The presence of symmetrically distinct hydrogen bonded molecule of water of crystallization and hydrogen bonded symmetrically distinct hydroxyl ions was inferred from the spectra in the derriksite unit cell. Approximate U–O bond lengths in uranyl and O–H_ _ _O hydrogen bond lengths were calculated from the Raman and infrared spectra of derriksite.