title: Raman spectroscopic study of the arsenite minerals ludlockite Pb Fe4(3+)As10O22 and schneiderhöhnite Fe2+Fe3(3+)As5(3+)O6.
abstract: Raman spectroscopy has been used to study the two arsenite minerals ludlockite and schneiderhöhnite, which have a common structural unit of pentameric arsenite groups. Raman bands for ludlockite are observed at 666, 674, 743, 756 and 798 cm(-1) and for schneiderhöhnite at 685, 719, 739, 774 and 798 cm(-1). Based upon DFT calculations, the band at 798 cm(-1) is attributed to nu(1) AsO(3)(2-) symmetric stretching vibration. Raman bands at 743 and 756 cm(-1) for ludlockite and at 719 and 739 cm(-1) for schneiderhöhnite are assigned to the nu(3) AsO(3)(2-) antisymmetric stretching vibration. Even though the minerals are very dark coloured to black in appearance, successful Raman spectra were collected.
authors: Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia.
authors: Silmarilly
authors: S
authors: Bahfenne
authors: Ray L
authors: RL
authors: Frost
mesh_terms: D001149:Arsenates / Q000032:analysis* / Q000737:chemistry; D018053:Arsenites / Q000032:analysis / Q000737:chemistry; D012987:Soil / Q000032:analysis; D013059:Spectrum Analysis, Raman
chemical_list: D001149:Arsenates; D018053:Arsenites; D012987:Soil; C015001:arsenite