Abstract The aim of this work is to find the effect of the cation M (Zn2+, Co2+, Cu2+, and Mg2+) on the optical properties of MFe2(P2O7)2 synthesized by solution combustion. The crystal structure of the powders was determined by X-ray diffraction (XRD), Infrared spectroscopy (IR), and Raman spectroscopy. The presence of Fe2+ and Fe3+ ions in the pigments was studied using Mossbauer spectroscopy (MS), these spectra showed at 298 K three well-defined Mossbauer doublets belonging to octahedral S1 site and S3 site of Fe3+ and trigonal prismatic S2 site of Fe2+, confirming the formation of ZnFe2(P2O7)2, CoFe2(P2O7)2 and MgFe2(P2O7)2 structures, while in CuFe2(P2O7)2 there is no presence of trigonal prismatic S2 site of Fe2+ ion. Therefore, the mechanism of color on the ZnFe2(P2O7)2, CoFe2(P2O7)2, and MgFe2(P2O7)2 structures are due to intervalence charge transfer between Fe2+ and Fe3+ ions. In contrast, on the CuFe2(P2O7)2 structure is due to d-d electronic transitions of the Cu2+ ion, these evidences can also be observed in their UV–Vis diffuse reflectance spectra. Moreover, the inorganic blue pigment MgFe2(P2O7)2, which is free of cobalt, copper, and zinc could be used as a pigment in applications of low temperatures.

中文翻译：

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通过溶液燃烧合成无机蓝色颜料 MFe2(P2O7)2：阳离子 M（Zn2+、Co2+、Cu2+ 和 Mg2+）对其光学性质的影响

摘要 本工作的目的是寻找阳离子 M（Zn2+、Co2+、Cu2+ 和 Mg2+）对溶液燃烧合成 MFe2(P2O7)2 光学性质的影响。通过X射线衍射(XRD)、红外光谱(IR)和拉曼光谱确定粉末的晶体结构。使用穆斯堡尔光谱 (MS) 研究了颜料中 Fe2+ 和 Fe3+ 离子的存在，这些光谱在 298 K 显示三个明确的穆斯堡尔双峰，属于 Fe3+ 的八面体 S1 位点和 S3 位点以及 Fe2+ 的三棱柱 S2 位点，证实ZnFe2(P2O7)2、CoFe2(P2O7)2 和 MgFe2(P2O7)2 结构的形成，而在 CuFe2(P2O7)2 中不存在 Fe2+ 离子的三角棱柱 S2 位点。因此，ZnFe2(P2O7)2、CoFe2(P2O7)2、和 MgFe2(P2O7)2 结构是由于 Fe2+ 和 Fe3+ 离子之间的间隔电荷转移。相反，在 CuFe2(P2O7)2 结构上是由于 Cu2+ 离子的 dd 电子跃迁，这些证据也可以在它们的 UV-Vis 漫反射光谱中观察到。此外，不含钴、铜和锌的无机蓝色颜料 MgFe2(P2O7)2 可用作低温应用中的颜料。