Chemical Preparation, Thermal Behavior and IR Studies of the New Chromium Diphosphate Hydrate and Crystal Structure of its Corresponding Anhydrous
Soufiane Zerraf, Mustafa Belhabra, Malika Tridane, Saïd Belaaouad, C Zaldo, M Mart, R Sol, M Aguil, F D z, P Roura, M Lpez De Miguel, C Muthuselvi, N Rathika, K Selvalaksh, Vibrational, F Allouche, W Selmi, M Zid, T Benlecheb, A Jouini, J Gcon, M Ferid, M Trabelsi-Ayadi, H Marouani, R Oubouaza, S Zerraf, A Ouasri, M Tridane, S Belaaouad, A Charaf, I Fahim, E Tace, M Tridane, M Radid, S Belaaouad, O Cherif, A Agrebi, S Alves, C Baleizo, J Farinha, F Allouche, S Zerraf, M Belhabra, M Tridane, S Belaaouad, R Oubouaza, H Marouani, S Zerraf, M Belhabra, A Ouasri, M Tridane, S Belaaouad, M Tridane, S Belaaouad, K Sbai, S Zerraf, M Tridane, S Belaaouad, D Louer, M Louer, D Louer, R Vargas, K Schlesinger, B Ziemer, W Hanke, G Ladwig, M Belhabra, S Zerraf, A Kheireddine, A Altomare, M Tridane, A Ouasri, M Radid, S Belaaouad, S Zerraf, M Tridane, S Belaaouad, S Zerraf, M Belhabra, A Kheireddine, R Lamsatfi, M Tridane, H Moutaabbid, B Baptiste, M Moutaabbid, S Belaaouad, H Marouani, M Tridane, El Majdi, S Zerraf, M Belhabra, S Belaaouad, S Makhloufy, M Tridane, H Marouani, S Zerraf, M Belhabra, A Cherqaoui, S Belaaouad, M Dewar
Abstract
Chemical preparation, thermal behavior, and IR studies are given for the diphosphate Cr4(P2O7)3.28H2O and its anhydrous form Cr4(P2O7)3. Cr4(P2O7)3.28H2O, is monoclinic P2/m with the following unit-cell dimensions : a = 16.169(1)Å, b = 9.336(5)Å, c = 9.446(4)Å, β = 124.796(5)°, and Z = 4. The total dehydration of Cr4(P2O7)3.28H2O, between 90°C and 450°C, leads to its anhydrous form, Cr4(P2O7)3. Cr4(P2O7)3 is isotopic to V4(P2O7)3, crystallizing in the orthorhombic system, space group Pmcn, Z = 4 with the following unit-cell dimensions: a = 7.25(2), b = 9.38(1)Å and c = 21.00(4)Å. Cr4(P2O7)3 is stable until its melting point at 1050°C. The thermal behavior of Cr4(P2O7)3.28H2O has been investigated and interpreted by comparison with IR absorption spectrometry and X-ray diffraction experiments.