Descripción teórica del dopado molecular de moléculas orgánicas conjugadas usando la Teoría del Funcional Densidad (DFT)

Abstract

Organic materials have become a valuable alternative for optoelectronic applications. These materials are classified as conjugated organic molecules (COM) and conjugated polymers (CP), which have been used as active layers in optoelectronic devices. Since semiconductor doping is a key factor in the operation of modern electronic devices, many efforts have been made since the last decade to obtain stable doped organic layers. Two models have emerged to explain the low efficiency of load generation due to doping of organic semiconductors: the full charge transfer model (ICT) and the hybrid charge transfer (HCT) model. The first model agrees with the adopted molecular doping of the inorganic semiconductor physics: full transfer of charge from the occupied organic orbital maximum (HOMO) of the organic semiconductor to the vacant molecular orbital minimum (LUMO) of the dopant molecule type P, and vice versa For N type doped. This project will deal, from a theoretical perspective, supported by computational calculations, relevant points such as: formation of polarones, internal transfer of charge, generation of free carriers, by means of an extensive use of the electronic structure calculation DFT, of the doping of the family of the Thiophenes: starting with monomers, the number of which is gradually increased (n = 1, 2, 3, ...., 8). As doping acceptor molecules, fluorinated derivatives of the tetracynequinodimethane prototype molecule (TCNQ) will be used.