The calculation of the heat of formation of Sm(Co1-x-yFexNiy)5 compound using homemade software in the framework of Miedema's model was carried out. In addition we investigated the influence of the probability of occupation the transition metals sites by 3d-ions, in particular, equiprobable distribution of 3d-ions among 2c and 3g sites and selective distribution Co/Ni-(2c), Fe-(3g). The maximal Fe and Ni doping ranges, where Sm(Co1-x-yFexNiy)5 phase with the CaCu5-type crystal structure stable, were estimated for both types of distribution. The corresponding values of the number of 3d-electrons per atom were 7.23 (Fe/Co/Ni-(2c, 3g)) and 7.3 (Co/Ni-(2c), Fe-(3g)). Based on calculation the Sm(Co1-x-yFexNiy)5 (x = 0.15, 0.3, 0.45; y = 0.05, 0.1, 0.15) melt-spun ribbons were synthesized. The maximal doping level of x = 0.5 and y = 0.2 was experimentally determined for Fe and Ni atoms, respectively. These values are in good agreement with the theoretical prediction, assumed equiprobable distribution of 3d-ions among transition metal sites. The best among the series in terms of energy product Sm(Co0.6Fe0.3Ni0.1)5 sample possesses a coercivity of 10.9 kOe and remanent magnetization of 51 emu/g.

中文翻译：

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Ni掺杂对Sm(Co1-xFex)5化合物稳定性的影响：热力学计算与实验


在Miedema模型框架下，利用自制软件计算了Sm(Co1-x-yFexNiy)5化合物的生成热。此外，我们还研究了 3d 离子占据过渡金属位点的概率的影响，特别是 3d 离子在 2c 和 3g 位点之间的等概率分布以及 Co/Ni-(2c)、Fe-(3g) 的选择性分布。对两种分布类型的最大 Fe 和 Ni 掺杂范围进行了估计，其中 Sm(Co1-x-yFexNiy)5 相具有稳定的 CaCu5 型晶体结构。每个原子的 3d 电子数的相应值为 7.23 (Fe/Co/Ni-(2c, 3g)) 和 7.3 (Co/Ni-(2c), Fe-(3g))。根据计算合成了Sm(Co1-x-yFexNiy)5 (x = 0.15, 0.3, 0.45; y = 0.05, 0.1, 0.15)熔纺带材。 Fe 和 Ni 原子的最大掺杂水平分别为 x = 0.5 和 y = 0.2。这些值与理论预测非常吻合，假设 3d 离子在过渡金属位点之间呈等概率分布。该系列中磁能积最好的Sm(Co0.6Fe0.3Ni0.1)5样品具有10.9 kOe的矫顽力和51 emu/g的剩磁。