Mono substituted pyrenes as multifunctional materials for OLED: Analysis of the substituent effects on the charge transport properties using DFT methods

In this work, with a general interest to understand the charge transport properties of mono substituted pyrene molecules which can be used as multifunctional materials in Organic Light Emitting Diodes (OLED), we have analyzed the charge transport properties calculated from DFT methods for a number of the mono substituted pyrene molecules whose crystal structures have been obtained from Cambridge structural data base (CSD). The data for the analysis was obtained by optimizing the geometries of the molecules in gas phase and subsequently generating the frontier orbitals and calculation of reorganization energies; transfer integrals in the solid state for various path ways were also calculated. The drift mobilities were then estimated from this data. The reasons for the variation of the drift mobilities in this group are then analyzed and the pattern reported. This work would be useful for generating new efficient pyrene derivatives and for improving existing ones for use in OLED.