Advances of ferrous and ferric Mossbauer recoilless fractions in minerals and glasses  

作　　者：Hongluo L.Zhang 

机构地区：[1]State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Beijing 100083,China

出　　处：《Geoscience Frontiers》2022年第2期78-89,共12页地学前缘（英文版）

基　　金：support from National Natural Science Foundation of China(41873067);Postdoctoral Science Foundation of China(2018M640160,2019T120120)。

摘　　要：Mössbauer spectroscopy has been used widely to characterize the ferric(Fe^(3+))and ferrous(Fe^(2+))proportions and coordination of solid materials.To obtain these accurately,the recoilless fraction is indispensible.The recoilless fractions(f)of iron-bearing minerals,including oxides,oxyhydroxides,silicates,carbonates,phosphates and dichalcogenides,and silicate glasses were evaluated from the temperature dependence of their center shifts or absorption area with the Debye model approximation.Generally,the resolved Debye temperature(θ_(D))of ferric iron in minerals,except dichalcogenides,through their center shifts ranging from 400 to 550 K,is significantly larger than ferrous iron ranging from 300 to 400 K,which is consistent with the conclusion from previous work.The resolved f(Fe^(3+))RT with the center shift model(CSM)ranges from 0.825 to 0.925,which is larger than that obtained for f(Fe^(2+))RT,which ranges from 0.675 to 0.750.Meanwhile,the θ_(D) and f resolved from temperature-dependence of absorption are generally lower than from center shifts,especially for ferric iron.The significant difference between f(Fe^(3+))and f(Fe^(2+))indicates the necessity of recoilless fraction correction on the Fe^(3+)/(Fe^(3+)+Fe^(2+))resolved from Mössbauer spectra.

关 键 词：Mossbauer spectroscopy Recoilless fraction Debye temperature Oxidation states Iron ratio 

分 类 号：TQ171.12[化学工程—玻璃工业] O657.3[化学工程—硅酸盐工业] P57[理学—分析化学]