Charge transport properties of triazole or cyclopentene triphenylene derivative discogen molecules
三唑和环戊烯苯并菲衍生物盘状液晶分子的电荷传输性质

Charge transport is one of the most important properties in organic electronic materials. On the basis of Marcus theory, the charge-transfer is the course of electron-electron interaction and electron-phonon interaction, and the greater the electron-phonon interaction coupling strength, the greater the reorganization energy is, which is not conducive to the charge transport. The greater the electron-electron interaction coupling strength, the greater the charge transfer matrix element is, which is beneficial to the charge transport. Charge transport properties of triphenylene derivative discogens molecules with a 1, 2, 3-triazole, 1, 2, 4-triazole or 1, 2, 3-trinitrogen-2, 3- cyclopenten side chain are investigated computationally. The results show that the electronic mobility and the hole mobility of 1, 2, 3-triazole triphenylene derivative are nearly equal, and the rate constant is 2× 1012s-1. The hole transfer rate constant of the 1, 2, 4-triazole triphenylene derivative molecules is 5× 1012s-1, which is ten times higer than the electronic transfer rate constant. Triphenylene containing 4, 5-dihydro-1, 2, 3-triazole has better electronic mobility but smaller hole mobility than triphenylene discogens containing 1, 2, 3-triazole or 1, 2, 4-triazole, and the electronic mobility is 3× 1012s-1, which is equal to ten times of the hole mobility. The hole transfer or electron transfer rate of the target molecules is affected mainly by the transfer matrix element, in other words, electron-electron interaction coupling strength determines the magnitude of mobility rate variation.