Charge transport in columnar mesophases of carbazole macrocycles

Abstract

Charge transport properties of a columnar mesophase of carbazole macrocycles are analyzed. Realistic morphologies are sampled using all-atom molecular dynamics simulations while charge transport is simulated using the kinetic Monte Carlo method with transfer rates obtained from the high temperature nonadiabatic limit of Marcus theory. It is shown that the molecular design with side chains pointing inside the macrocycle allows close approach between molecules of neighboring columns, thus enabling three-dimensional transport and helping to circumvent charge trapping on structural defects.

Microscopic Simulations of Charge Transport in Disordered Organic Semiconductors

“…This molecular orbital overlap (MOO) method has been applied successfully to study charge transport, for instance, in discotic liquid crystals, 31,37,38 polymers,(36) or partially disordered organic crystals. 33−35 …”

Modeling of Organic Light Emitting Diodes: From Molecular to Device Properties

“…[ 80 ] In some cases the explicit evaluation of the dimer Hamiltonian can be avoided by employing semiempirical methods. [ 18,19,84,85 ] Depending on the fi rstprinciples method and approximations used, computed electronic coupling elements can easily vary by a factor of ten. Together with the energetic landscape, they constitute one of the main factors which infl uence charge transport in organic semiconductors.…”

Self-assembled cyclic oligothiophene nanotubes: Electronic properties from a dispersion-corrected hybrid functional

“…III to validate our chosen approach). It is important to mention that there has also been recent work in carbozole macrocycles 12 and a similar study on cyclic oligothiophene multimers 58 using different theoretical methods. However, both of these studies focused only on isolated molecular aggregates and did not address band-structure properties in a fully periodic nanotube geometry.…”

“…10 Compared to conventional carbon nanotubes bonded via strong covalent interactions, cyclic oligothiophene nanotubes are held together along the tube axis via purely noncovalent interactions, lending to facile self-assembly from individual cyclic monomers. 11 In addition, since the electronic interactions between adjacent nanotubes can be selectively tuned via chemical functionalization with side chains, 12 these materials in principle can be tailored to modulate quasi-one-dimensional electronic transport along the tube axis. [13][14][15] As a result, self-assembled cyclic oligothiophene nanotubes are potentially a new class of organic nanotubes with tunable electronic properties which can be utilized as semi-conducting materials in nanoelectronic devices.…”