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Ａｌ和Ｔｉ对Ｍｇ２Ｎｉ结构中部分Ｍｇ的取代，得到与Ｍｇ２Ｎｉ晶体结构不同的新型合金．多晶Ｘ射线结构分析表明，其化学式为Ｍｇ３ＭＮｉ２（Ｍ＝Ｔｉ，Ａｌ），立方晶系，空间群Ｆｄ３ｍ， Ｚ＝１６，４８个Ｍｇ坐落在４８（ｆ），１６个 Ｍ（Ｍ＝Ａｌ， Ｔｉ）坐落在１６（ｄ）位，３２个Ｎｉ坐落在３２（ｅ）位，Ｍｇ３ＡｌＮｉ２的晶胞参数ａ＝１．１５４７４（２）ｎｍ， Ｍｇ３ＴｉＮｉ２的ａ＝１．１６１７８（２）ｎｍ．与Ｍｇ２Ｎｉ相比，Ｍｇ３ＭＮｉ２合金的晶体密度更大，Ｍｇ－Ｎｉ键长更长，吸放氢温度降低，循环寿命延长．
The substitution of Al and Ti for some Mg in the Mg2Ni structure gives a new alloy with a different crystal structure from Mg2Ni. Polycrystalline X-ray structure analysis shows that the chemical formula is Mg3MNi2 (M = Ti, Al), cubic system, space group Fd3m, Z = 16,48 Mg is located at 48 (f), 16 M Ti is located at 16 (d) and 32 Ni are located at 32 (e). The unit cell parameters of Mg3AlNi2 are a = 1.15474 (2) nm and a = 1.16178 (2) nm for Mg3TiNi2. Compared with Mg2Ni, Mg3MNi2 alloy has higher crystal density, longer Mg-Ni bond length, lower hydrogen absorption and desorption temperature and longer cycle life.