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共轭聚合物中的电子可以分为π电子和σ电子两大类 .当格点发生畸变时 ,σ电子能量的变化总是倾向于阻碍畸变发生 .因此系统是否产生畸变将取决于π电子的能量变化 .我们的结果表明 ,对一类典型的共轭聚合物 (Poly Cngroup) ,当n >2时 ,畸变后π电子的能量变化同样倾向于阻碍畸变发生 .因此 ,n >2的聚合物不发生Peierls畸变 .不过当考虑较远邻作用后 ,n为偶数的能级简并被解除 ,因为它们是一种偶然简并 ,而n为奇数的分子仍然保持能带的简并性 ,即无能隙能带结构 .这种简并性来源于n为奇数的分子具有滑移平面对称性 ,因而它是内禀的 .从这种意义上说 ,所有n >2且为奇数的Poly Cn 群分子可能成为有机超导材料的候选物 .
Electrons in conjugated polymers can be divided into two categories: π electron and σ electron. When the lattice point is distorted, the change of σ electron energy always tends to hinder the distortion, so whether the system will produce distortion will depend on the π electron Energy Variation Our results show that for a typical type of conjugated polymer (Poly Cngroup), the energy change of π electrons after distortion also tends to hinder the distortion when n> 2. Therefore, polymers with n> 2 Peierls distortion does not occur, but when considering the effects of more distant neighbors, the energy level degeneracy of n is even, as they are an occasional degeneracy while the molecules of n are odd numbers while still maintaining the degeneracy of the energy band, ie Anergy-gap band structure. This degeneracy originates from n-odd molecules having a sliding plane symmetry and is therefore intrinsic. In this sense, all Polycn groups with n> 2 and an odd number Molecules may become candidates for organic superconducting materials.