RESUMO
Charge hopping based on Marcus theory is often used to predict charge carrier mobilities in organic crystals, although it is known to systematically underestimate the values. Here we show that this deficiency may lie on a fundamental aspect of quantum statistical averages, rather than on the approximation itself. Under adequate Boltzmann weighing procedure used to evaluate electron and hole transfer integrals, a kinetic Monte Carlo model is employed to describe mobilities in an azacene derivative. The values are in good agreement with experimental data suggesting that the evaluation of transfer integrals may be the weak link in hopping transport models.
RESUMO
In this work, we investigate the adsorption process of CO2 in graphene quantum dots from the electronic structure and spectroscopic properties point of view. We discuss how a specific doping scheme could be employed to further enhance the adsorbing properties of the quantum dots. This is evaluated by considering the depth of the potential well, the spectroscopic constants, and the lifetime of the compound. Electronic structure calculations are carried out in the scope of the density functional theory (DFT), whereas discrete variable representation (DVR) and Dunham methodologies are employed to obtain spectroscopic constants and hence the lifetimes of the systems. Our results suggest that nitrogen-doped graphene quantum dots are promising structures as far as sensing applications of CO2 are concerned. Graphical Abstract Adsorption mechanism of the CO2 molecule in (a) a pristine and (b) a nitrogendoped Graphene Quantum Dot.