采用杂化密度泛函（ＤＦＴ）之Ｂ３ＬＹＰ／６－３１１Ｇ方法研究了ＮｘＨｙ－Ｆｅ（ｘ＝０～２，ｙ＝０～３）配位簇的几何结构和振动光谱。讨论了在纯铁催化剂上，氮分子和氢分子逐步合成氨的反应机理。结果表明，合成氨过程可能经历Ｎ２和Ｎ２Ｈ２物种。在优化结构的基础上，计算了各个模型的振动频率并解释了有关实验结果。 The geometry and vibrational spectra of NxHy-Fe (x = 0 ~ 2, y = 0 ~ 3) coordination clusters have been studied by B3LYP / 6-311G method using hybrid density functional theory (DFT) The reaction mechanism of the gradual synthesis of ammonia between nitrogen molecules and hydrogen molecules on pure iron catalyst was discussed. The results show that the ammonia process may experience N2 and N2H2 species. Based on the optimized structure, the vibration frequency of each model was calculated and the relevant experimental results were explained.