Synthesis and physicochemical characterizations of a new valence-mixed pyrophosphate: Cu 0.5 Zn 0.5 Fe 2 (P 2 O 7 ) 2

Synthesis, Structural Studies, and Magnetic Properties of a New Mixed-Valence Diphosphate: Zn2+5Fe3+2(P2O7)4

“…[ 2 7 -2 9 ] for Fe 4 ( P 2 O 7 ) 2 , Zn 2 F e ( P O 4 ) 2 • 4 H 2 O , ZnFe 2 (P 2 O 7 ) 2 , and Zn 0.5 Cu 0.5 Fe 2 (P 2 O 7 ) 2 , while the bands observed at 960 and 910 cm −1 are attributed, respectively, to the anti-symmetric and symmetric stretching vibrations of the POP bridge [27][28][29]. The deformation vibrations of the diphosphate moiety and the Zn-O and Fe-O stretching modes give rise to bands at frequencies within the 600-450 cm −1 range, also in good agreement with previously reported data [13,14,[26][27][28][29]. a From ref.…”

“…present the room temperature infrared and Raman spectra of Zn 5 Fe 2 (P 2 O 7 ) 4 , respectively. The comparison of these spectra with those previously reported for other diphosphates[13,14,[24][25][26][27][28][29] allowed characterization of the vibrations associated with the diphosphate fragment, as well as those associated with the Zn-O and Fe-O moieties.…”

“…The stretching modes of the terminal PO 3 2− groups give rise to two broad intense pairs of bands, at 1273/1081 cm −1 and 1011/938 cm −1 , which are ascribed to the anti-symmetric and symmetric stretching modes of these groups, respectively. In turn, the symmetric P-O stretching mode of the bridges is observed at 850 cm −1 , while the bands at 576, 551, and 521 cm −1 are attributed to deformation modes of the PO 3 2− groups [13,14].…”

“…The procedure used to synthesize the Zn 5 Fe 2 (P 2 O 7 ) 4 pyrophosphate follows that described in refs. [13,14] and has been designated as "dry way" method. Briefly, stoichiometric amounts of ZnO, Fe 2 O 3 , and (NH 4 )HPO 4 were used as starting materials.…”