The quantum charge transport calculations at metal–molecule–metal junctions lead to various electronic properties suitable in the field of miniaturization. Finite bias-dependent conductivity is calculated through porphyrin, hexaphyrin, and hexathia[26π]annulene molecular junction devices connected to the metallic or semiconducting electrode using non-equilibrium Green's function technique based on the density functional theory method. The ( I − V) characteristic curves calculated for various donor–insulator–acceptor (D–σ–A) devices show a Ohmic, diode, or rectifier-like nature depending on the donor acceptor substitution effect in the above molecules connected to the electrode. The rectification ratio R ( I + / I − or I − / I +) calculated for such devices varies from 2 to 70, and maximum R is calculated for the D–A-substituted porphyrin molecular junction. The I − V characteristics, rectification, and negative differential resistance effect found in such devices are well analyzed by projected density of states and molecular-projected self-consistent Hamiltonian eigenstate, local density of state calculations. Molecular conductivity calculations in D–σ–A devices using porphyrin, hexaphyrin, and hexathia[26π]annulene show promise in the field of molecular electronics and memory storage devices.

中文翻译：

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卟啉、六卟啉和六硫杂[26π]环烯分子结器件输运性质的第一性原理研究

金属-分子-金属结处的量子电荷传输计算导致了适用于小型化领域的各种电子特性。使用基于密度泛函理论方法的非平衡格林函数技术，通过连接到金属或半导体电极的卟啉、六卟啉和六硫杂 [26π] 环烯分子结装置计算有限偏置相关的电导率。为各种供体-绝缘体-受体 (D-σ-A) 器件计算的 ( I - V) 特性曲线显示出欧姆、二极管或类似整流器的性质，具体取决于连接到电极的上述分子中的供体受体取代效应. 为此类器件计算的整流比 R ( I + / I - 或 I - / I +) 从 2 到 70 不等，最大 R 是为 D-A 取代的卟啉分子连接计算的。通过投影状态密度和分子投影自洽哈密顿本征态、局部状态密度计算，可以很好地分析在此类器件中发现的 I - V 特性、整流和负微分电阻效应。使用卟啉、六卟啉和六硫杂 [26π] 环烯的 D-σ-A 器件中的分子电导率计算在分子电子学和存储设备领域显示出前景。