基于密度泛函理论,从头计算了具有ThCr2Si2型四方晶系的稀土金属化合物YFe2B2体相的物理特性.能量计算结果表明YFe2B2体相处于顺磁金属态;而能带结构、态密度、布居数以及差分电荷分布的计算结果表明Y原子的5s,5p电子具有很强的局域性;Fe原子的3d电子和B的1s,2s和2p电子强烈耦合,使得最近邻Fe原子与B原子形成了Fe—B共价键;最近邻的两个Fe原子之间由于其3d电子相互作用形成金属键,Fe原子与Y原子的键合方式为反键态;说明YFe2B2的基态为顺磁三元合金. Based on the density functional theory (DFT), the physical properties of the YFe2B2 phase with the ThCr2Si2 tetragonal system have been ab initio calculated. The energy calculations show that the YFe2B2 phase is in the paramagnetic metal state, while the band structure, density of states, And the results of the differential charge distribution show that the 5s and 5p electrons of Y atom are strongly localized. The 3d electrons of Fe atom and the 1s, 2s and 2p electrons of B are strongly coupled so that the nearest Fe atoms and B atoms form Fe-B covalent bond; the two nearest neighbor Fe atoms due to their 3d electronic interactions to form a metal bond, Fe atom and Y atom bonding mode is antibonding state; YFe2B2 ground state of the paramagnetic ternary alloy .