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本实验测定了新型钼（钨）－铁－硫簇合物（ｌ）（Ｅｔ４Ｎ）［ＭｏＦｅ２（μ３－Ｓ）２（ＣＯ）８（Ｓ２ＣＮＥｔ２）］和（２）（Ｅｔ４Ｎ）［ＷＦ２（μ２－Ｓ）２（ＣＯ）５（Ｓ２ＣＮＥｔ２）］的穆斯堡尔谱和晶体结构，它们分子中的两个铁原子是等价的，所以都只有一组对称的四极分裂双峰．这个结果与单晶结构分析一致．经计算机拟合后的穆斯堡尔参数（７７Ｋ时）为：对于（１），化学位移δ＝０．０８±０．００４ｍｍ／ｓ，四级裂距△ＥＱ＝０．９６５±０．００４ｍｍ／ｓ，线宽Г＝０．３２０±０．００４ｍｍ／ｓ；对于（２），δ＝０．００７±０．００４ｍｍ／ｓ，△ＥＱ＝０．８３４±０．００４ｍｍ／ｓ，Г＝０．３７１±０．００４ｍｍ／ｓ．化学位移值是相对于α－Ｆｅ的．它们的晶体结构已由Ｘ射线衍射测定．它们都属三斜晶系，空间群．从穆斯堡尔参数可确定簇合物（１）和（２）的分子中铁原子都是＋２价低自旋态（Ｓ＝０）．
In the present study, the effects of the new molybdenum (tungsten) -iron-sulfur cluster (Et4N) [MoFe2 (μ3-S) 2 (CO) 8 (S2CNEt2)] and (2) (Et4N) [WF2 S) 2 (CO) 5 (S2CNEt2)], the two iron atoms in their molecule are equivalent, so there is only one set of symmetrical quadrupole bimodal peaks. This result is consistent with the single crystal structure analysis. The computer-fitted Mössbauer parameters (at 77 K) are: For (1), chemical shift δ = 0.08 ± 0.004 mm / s, fourth order crack ΔEQ = 0.965 ± 0.004 mm / S, linewidth Γ = 0.320 ± 0.004 mm / s; δ = 0.007 ± 0.004 mm / s for (2), ΔEQ = 0.834 ± 0.004 mm / s, .371 ± 0.004 mm / s. The chemical shift value is relative to α-Fe. Their crystal structure has been determined by X-ray diffraction. They are triclinic, space group. From the Mössbauer parameters, it can be confirmed that all the iron atoms in the clusters (1) and (2) are in the +2 low spin state (S = 0).