Raman spectra of lead molybdate single crystals

Thermally modified molybdenum oxide as a potential sorbent for the removal of metal cations from aqueous solutions

“…The XRD pattern of the new phase can be indexed as the tetragonal scheelite-type structure of Wulfenite PbMoO 4 (in the case of U-loaded material the structure of umohoite UMoO 6 Á2H 2 O was observed) [25,26,64,65]. The XRD findings were also confirmed by Raman spectroscopy (Fig.…”

Synthesis of lead molybdate and lead tungstate via microwave irradiation method

“…Finally, one A u and one E u are acoustic vibrations [8,[18][19][20]. The 13 Raman active vibrations, seven modes are internal modes of the [MO 4 ] 2À (MQMo and W) tetrahedra and remaining six are external modes; two rotations of A g symmetry and four translation of 2B g and 2E g symmetries [19,20]. n 3 (E g ), n 3 (B g ) and n 1 (A g ) vibrations of PbMO 4 (MQMo and W) were summarized in Table 5.…”

“…This fact reveals that [MO 4 ] 2À (MQMo and W) bond is much stronger than the bond with Pb ions. The A g mode, at 169.11 cm À1 for PbMoO 4 and 178.40 cm À1 for PbWO 4 which [MO 4 ] 2À (MQMo and W) ion rotates about z-axis is much weaker than other modes[8,[18][19][20]. It was quite ambiguous without A+B, modes.…”

Variable-Temperature and High-Pressure Micro-Raman Spectra of Inorganic Artists' Pigments: CrystallineWulfenite, Lead(II) Molybdate(VI), PbMoO4

“…1. Unlike in the previous work, where other excitation lasers were used, [4][5][6][7] this spectrum was obtained using a near-IR 785 nm diode laser. From a group theoretical treatment of crystalline ABO 4 tungstates and molybdates, including PbMoO 4 , all are members of the scheelite mineral family and have C 4h crystal symmetry.…”

“…[5] Variable-temperature micro-Raman measurements were previously reported to investigate the temperature dependence on the 13 Raman-active modes of PbMoO 4 . [6,7] One group was particularly interested in studying the effect of temperature on the electrical conductivity of the metal and recorded the Raman spectra at 100 C intervals from room temperature up to 700 C. [6] The other study included temperature measurements for the À196 C to 200 C range. [7] Here we report unique high-and low-temperature analyses of wulfenite that discuss spectral changes to all the Raman-active vibrational modes, whereas the previous literature only focused on selected a g and e g [6] and a g [7] modes.…”