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对３个合成的含Ｆｅ~３＋的铁硅酸盐尖晶石γ－Ｆｅ_２ＳｉＯ_４进行了电子探针分析，并在２９８，１５０和９５Ｋ的温度下对它们进行了Ｍｏｓｓｂａｕｅｒ谱的测试．每个温度下的Ｍｏｓｓｂａｕｅｒ谱均由两个双峰组成．这两个双峰分别被指派给八面体位置上的Ｆｅ~２＋和四面体位置上的Ｆｅ~３＋，并且根据Ｍｏｓｓｂａｕｅｒ吸收面积给出了占位结果表明，Ｆｅ~３＋和少量的Ｓｉ~４＋分别占据在四面体和八面体位置上．根据Ｍｏｓｓｂａｕｅｒ分析所得到的占位，使用经过修正的公式，计算了八面体和四面体位置的平均键长．在此基础上，八面体和四面体的平均键长进而被用来计算含Ｆｅ~３＋的γ－Ｆｅ_２ＳｉＯ_４的晶胞参数和氧参数．此外，使用次近邻效应解释了含Ｆｅ~３＋的γ－Ｆｅ_２ＳｉＯ_４Ｍｏｓｓｂａｕｅｒ谱的Ｆｅ~３＋谱线的宽化现象。
Three synthetic ferrosilicate spinel γ-Fe 2 SiO 4 containing Fe 3+ were analyzed by electron microprobe and their Mossbauer spectra were tested at 298, 150 and 95K. The Mossbauer spectrum at each temperature consists of two bimodal peaks. The two bimodals were assigned to Fe ~ 2 + at the octahedral site and Fe ~ 3 + at the tetrahedron site, respectively, and the placeholder results were given according to the Mossbauer absorption area. The results show that Fe ~ 3 + and a small amount of Si ~ 4 + Occupy tetrahedral and octahedral positions. Based on the placeholder obtained by the Mossbauer analysis, the average bond length of octahedral and tetrahedral positions was calculated using a modified formula. On this basis, the average bond length of octahedron and tetrahedron is further used to calculate the unit cell parameters and oxygen parameters of γ-Fe 2 SiO 4 with Fe 3+. In addition, the second nearest neighbor effect is used to explain the broadening of the Fe 3+ line in the γ-Fe 2 SiO 4 Mossbauer spectrum of Fe 3+.