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用紧束缚近似的EHMO方法对α-MTDTPY·TCNQ(1)、β-MTDTPY·TCNQ(2)及MTDTPY·CHL(3)三种电荷转移复合物晶体的电子能带进行了计算.在1中,电子施体(D)分子MTDTPY及受体(A)分子TCNQ形成交替重叠的一维分子柱(M),柱间无净电荷转移.能隙.E_G=0.15 eV,载流子的产生主要来自热激发.在2及3中,电子施体(D)MTDTPY及受体(A)TCNQ及CHL分子分别形成相对独立的D及A一维分子柱,载流子的产生主要来自柱间的电荷转移.由电子能带结构及关于载流子迁移的Frohlich-Sewell公式,得出上述三种晶体的室温电导率之比为σ_1∶σ_2∶σ_3=3.72×10~(-10)∶1∶1.15,与实验事实基本一致.关于各分子柱对σ的贡献,2中D柱∶A柱～10~3∶1;3中D柱∶A柱～2∶1.根据计算结果,本文还对载流子的迁移机理进行了讨论.
The electron bands of α-MTDTPY · TCNQ (1), β-MTDTPY · TCNQ (2) and MTDTPY · CHL (3) complexes were calculated by using the tight-binding EHMO method. , The electron donor (D) molecule MTDTPY and the acceptor (A) molecule TCNQ form alternately overlapping one-dimensional molecular column (M) with no net charge transfer between the energy gaps .E_G = 0.15 eV, carrier generation mainly In the 2 and 3, the electron donor (D) MTDTPY and the receptor (A) TCNQ and CHL molecules form relatively independent D and A one-dimensional molecular columns, respectively, and the generation of carriers mainly comes from between the columns Charge transfer. From the electronic band structure and the Frohlich-Sewell formula on the carrier transport, we can get the ratio of the room temperature conductivity of these three kinds of crystals is σ_1: σ_2: σ_3 = 3.72 × 10 -10: 1: 1.15, which is basically consistent with the experimental facts.For the contribution of each molecular column to σ, D column in 2: A column ~ 10 ~ 3: 1 and D column in column 3: A column ~ 2: 1.According to the calculation results, Carrier transport mechanism is discussed.