中文摘要：

采用基于密度泛函理论（DFT）的平面波赝势方法的第一性原理计算,对过渡金属铜元素进行总能量计算,能量计算精度取为0.01 eV.通过分析分波能带展宽与能带电子对总能量的贡献,讨论了不同压强范围下第一性原理计算时铜原子芯态和价态的划分.结果显示,当压强增加到约139.3 GPa时,3p电子因能带的展宽对总能的贡献将不能忽略,需将作为价电子处理.计算结果为进一步高压下的物性的第一性原理研究提供了依据.

英文摘要：

By using the pseudopotentials and plane-wave method, first-principles calculation method based on the density-functional theory（DFT） is performed for the total energy calculations of the transition metal copper. The computational precision of the energy is set to 0.01 eV and the total-energy is calculated. The results show that the 3p state should be treated as valence state when pressure is higher than 139.3 GPa.