中文摘要：

与 Pa3 和 P1 的空间组一起的 FeS2 的电子结构和性质被密度学习功能的理论。概括坡度的近似交换关联功能与一个飞机 wave-ultrasoft pseudopotential 代表一起被使用。计算结果证明差别在在 Pa3 和 P1 晶体之间的电子结构和性质被观察。当 P1 的光吸收的绝缘的常数，传导性，折射索引，扑灭系数，和紧张比 Pa3 的那些大时， P1 的乐队差距和精力损失是比 Pa3 水晶的那些小的。这些行为在对称， Pa3 和 P1 晶体的原子安排，和每个单位的 Mulliken 契约人口被归因于差别。

英文摘要：

The electronic structure and properties of FeS2 with the space groups of Pa3 and P1 were studied by the density functional theory. The generalized-gradient approximation exchange-correlation functional was used in conjunction with a plane wave-ultrasoft pseudopotential representation. Calculation results show that differences are observed in electronic structures and properties between Pa3 and P1 crystals. The band gap and energy loss of P1 are smaller than those of Pa3 crystal, while the dielectric constant, conductivity, refractive index, extinction coefficient, and intensity of optical absorption of P1 are larger than those of Pa3. These behaviors are attributed to the differences in symmetry, atomic arrangement, and Mulliken bond population of each unit for Pa3 and P1 crystals.