Columnar mesophases of hexabenzocoronene derivatives. II. Charge carrier mobility.
Combining atomistic molecular dynamic simulations, Marcus-Hush theory description of charge transport rates, and master equation description of charge dynamics, we correlate the temperature-driven change of the mesophase structure with the change of charge carrier mobilities in columnar phases of hexabenzocoronene derivatives. The time dependence of fluctuations in transfer integrals shows that static disorder is predominant in determining charge transport characteristics. Both site energies and transfer integrals are distributed because of disorder in the molecular arrangement. It is shown that the contributions to the site energies from polarization and electrostatic effects are of opposite sign for positive charges. We look at three mesophases of hexabenzocoronene: herringbone, discotic, and columnar disordered. All results are compared to time resolved microwave conductivity data and show excellent agreement with no fitting parameters.
Kirkpatrick
James
J
Max-Planck-Institut fur Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany. james.kirkpatrick@imperial.ac.uk
Marcon
Valentina
V
Kremer
Kurt
K
Nelson
Jenny
J
Andrienko
Denis
D
D000465:Algorithms; D003198:Computer Simulation; D050866:Liquid Crystals / Q000737:chemistry; D008872:Microwaves; D008956:Models, Chemical; D015394:Molecular Structure; D009038:Motion; D044367:Phase Transition; D011083:Polycyclic Compounds / Q000737:chemistry*; D011789:Quantum Theory; D012399:Rotation; D055672:Static Electricity; D013696:Temperature; D013997:Time Factors
D011083:Polycyclic Compounds; C507240:hexa-peri-hexabenzocoronene