Raman spectroscopic study of the tellurite mineral: poughite Fe 2 3+ SO 4 (TeO 3 ) 2 ·3H 2 O—a multi‐anion mineral

Poughite Fe 2 3+ SO 4 (TeO 3 ) 2 ·3H 2 O, a multi‐anion mineral containing both tellurite and sulfate units has been studied by Raman spectroscopy. Raman bands at 655 cm −1 is attributed to (TeO 3 ) 2− stretching bands. The intense sharp Raman band at 1026 cm −1 is assigned to the ν 1 (SO 4 ) 2− symmetric stretching mode, while the bands at 1078, 1152 and 1187 cm −1 are assigned to the ν 3 (SO 4 ) 2− antisymmetric stretching mode. The spectral region 100 to 600 cm −1 displays the bands, which are attributable to the (SO 4 ) 2− and (TeO 3 ) 2− bending modes. Some evidence from very low intensity Raman bands in the 2800–3600 cm −1 region provides evidence of proton‐tellurite anion interactions. Hydrogen bond distances have been calculated. Copyright © 2008 John Wiley & Sons, Ltd.