Jocelyne Bouzaid

Raman Spectroscopic Study of the Molybdate Mineral Szenicsite and Comparison with Other Paragenetically Related Molybdate Minerals

Abstract The molybdate‐bearing mineral szenicsite, Cu3(MoO4)(OH)4, has been studied by Raman and infrared spectroscopy. A comparison of the Raman spectra is made with those of the closely related molybdate‐bearing minerals, wulfenite, powellite, lindgrenite, and iriginite, which show common paragenesis. The Raman spectrum of szenicsite displays an intense, sharp band at 898 cm−1, attributed to the ν1 symmetric stretching vibration of the MoO4 units. The position of this particular band may be compared with the values of 871 cm−1 for wulfenite and scheelite and 879 cm−1 for powellite. Two Raman bands are observed at 827 and 801 cm−1 for szenicsite, which are assigned to the ν3(E g ) vibrational mode of the molybdate anion. The two MO4 ν2 modes are observed at 349 (B g ) and 308 cm−1 (A g ). The Raman band at 408 cm−1 for szenicsite is assigned to the ν4(E g ) band. The Raman spectra are assigned according to a factor group analysis and are related to the structure of the minerals. The various minerals mentioned have characteristically different Raman spectra.

Bis[cis-bis-(diphenyl-phosphino)ethene]copper(I) dichloridocuprate(I).

The crystal structure of the title compound, [Cu(C26H22P2)2][CuCl2], is composed of discrete Cu(dppey)2]+ cations [dppey is cis-bis(diphenylphosphino)ethene] and [CuCl2]− anions. The tetrahedral Cu(P—P)2 core of the [Cu(dppey)2]+ cation is distorted, with Cu—P bond lengths ranging from 2.269 (1) to 2.366 (1) Å. The five-membered –Cu—P—CH=CH—P– rings adopt envelope conformations, with the Cu atom lying 0.38 and 0.65 Å out of the P—C=C—P planes. The Cu—Cl distances in the [CuCl2]− anion are 2.094 (2) and 2.096 (2) Å, with a Cl—Cu—Cl angle of 176.81 (7)°.