论文部分内容阅读
采用基于密度泛函理论的第一性原理方法,研究了CeFe_2、CeFe_5、Ce_2Fe_(17)三种化合物的生成焓、结合能、电子结构、弹性性能、力学性能及德拜温度。生成焓和结合能表明三种化合物均具有热力学稳定性,且Ce_2Fe_(17)具有最好的化合物形成能力;态密度图表明三种化合物的成键方式相似,成键电子主要是由Ce的6s、5p、4f轨道电子与Fe的3d轨道电子贡献;差分电荷密度图得出三种化合物均有金属键、离子键、共价键三种键构成;杨氏模量、剪切模量、德拜温度、理论硬度的大小顺序进一步得出Ce_2Fe_(17)具有最好的力学、热力学稳定性。
The enthalpies of formation, the binding energy, the electronic structure, the elastic properties, the mechanical properties and the Debye temperature of CeFe_2, CeFe_5 and Ce_2Fe_ (17) were studied by the first principle method based on density functional theory. The formation enthalpies and binding energies show that all the three compounds have thermodynamic stability, and Ce_2Fe_ (17) has the best compound formation ability. The state density diagrams show that the bonding energies of the three compounds are similar, and the bonding electrons are mainly composed of 6s , 5p, 4f orbital electrons and Fe orbitals. The differential charge density maps show that all three compounds have metal bonds, ionic bonds and covalent bonds. Young’s modulus, shear modulus, Thanks to the order of temperature and theoretical hardness, it is further concluded that Ce 2 Fe 17 has the best mechanical and thermodynamic stability.