%0 Journal Article %1 WOS:000312965800023 %A Saraiva, G D %A Luz-Lima, C %A Freire, P T C %A de Castro, A J Ramiro %A de Sousa, G P %A Melo, F E A %A Silva, J H %A Filho, J Mendes %C RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS %D 2013 %I ELSEVIER %J JOURNAL OF MOLECULAR STRUCTURE %K Infrared; Molybdate; Phase Tungstates; X-ray; transition} {Raman; %P 154-161 %R 10.1016/j.molstruc.2012.08.024 %T Vibrational and structural properties in the dihydrate sodium tungstate and in the dihydrate sodium molybdate crystals %V 1033 %X Temperature-dependent vibrational (Raman and infrared) spectroscopy and X-ray diffraction studies have been performed on polycrystalline Na2WO4 center dot 2H(2)O and Na2MoO4 center dot 2H(2)O crystals. Raman data at low temperature 13-300 K for sodium tungstate Na2WO4 center dot 2H(2)O was compared with the sodium molybdate Na2MoO4 center dot 2H(2)O. The infrared and the X-ray diffraction obtained in the 80-300 K suggest that both crystals have undergone conformational changes connected with an increase in the Raman intensity of NaO6 modes and the libration modes of water molecules at about 100-120 K. Additionally, Raman spectroscopy measurements of Na2WO4 center dot 2H(2)O under hydrostatic pressure (from 0 to 5 GPa) were performed. The pressure-dependent studies indicate the starting orthorhombic structure is stable in the 0.0-3.2 GPa pressure range, and undergoes a phase transition at about 3.9 GPa, associated with rotation of WO4-2 units. (C) 2012 Elsevier B.V. All rights reserved.

@article{WOS:000312965800023, abstract = {Temperature-dependent vibrational (Raman and infrared) spectroscopy and X-ray diffraction studies have been performed on polycrystalline Na2WO4 center dot 2H(2)O and Na2MoO4 center dot 2H(2)O crystals. Raman data at low temperature 13-300 K for sodium tungstate Na2WO4 center dot 2H(2)O was compared with the sodium molybdate Na2MoO4 center dot 2H(2)O. The infrared and the X-ray diffraction obtained in the 80-300 K suggest that both crystals have undergone conformational changes connected with an increase in the Raman intensity of NaO6 modes and the libration modes of water molecules at about 100-120 K. Additionally, Raman spectroscopy measurements of Na2WO4 center dot 2H(2)O under hydrostatic pressure (from 0 to 5 GPa) were performed. The pressure-dependent studies indicate the starting orthorhombic structure is stable in the 0.0-3.2 GPa pressure range, and undergoes a phase transition at about 3.9 GPa, associated with rotation of WO4-2 units. (C) 2012 Elsevier B.V. All rights reserved.}, added-at = {2022-05-23T20:00:14.000+0200}, address = {RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS}, author = {Saraiva, G D and Luz-Lima, C and Freire, P T C and de Castro, A J Ramiro and de Sousa, G P and Melo, F E A and Silva, J H and Filho, J Mendes}, biburl = {https://www.bibsonomy.org/bibtex/26d3e9df0ce31d2f9000b6f9c9e0c078f/ppgfis_ufc_br}, doi = {10.1016/j.molstruc.2012.08.024}, interhash = {d50c117bf67bf5b38931d21c21f7a27f}, intrahash = {6d3e9df0ce31d2f9000b6f9c9e0c078f}, issn = {0022-2860}, journal = {JOURNAL OF MOLECULAR STRUCTURE}, keywords = {Infrared; Molybdate; Phase Tungstates; X-ray; transition} {Raman;}, pages = {154-161}, publisher = {ELSEVIER}, pubstate = {published}, timestamp = {2022-05-23T20:00:14.000+0200}, title = {Vibrational and structural properties in the dihydrate sodium tungstate and in the dihydrate sodium molybdate crystals}, tppubtype = {article}, volume = 1033, year = 2013 }