Evolution of the model to describe semiclassically the charge dynamics in organic semiconductor. (a) in Ref. 29, we considered a one-dimensional array with one state per site, (b) in Ref. 33, we considered more states per site in one dimension; and (c) the formalism presented in this work is for an arbitrary number of states per sites and dimensions.
The models considered in this paper. (a) The 1D chain of rubrene molecules, with interaction only between nearest neighbors. (b) The ab plane of rubene with indicated two molecules in the unit cell. (c) The coupling pattern of the molecules in the rubrene plane with two couplings of type A and four of type B per unit cell. The coupling type A in the plane is identical to the coupling between neighbors in the rubrene chain. The conventional unit cell vectors a and b, of length 14.4 and 7.2 Å, respectively, are also shown with the Cartesian directions x and y used to define the mobility tensor.
(a) DOS (per molecule) and (b) energy resolved localization length of a one-dimensional chain or rubrene molecules at 300 K. The dashed line in panel (a) indicates the DOS in the absence of electron-phonon coupling (or at 0 K in the semiclassical limit).
(a) DOS (per molecule) and (b) energy resolved localization length for the two-dimensional model of the ab plane of rubrene at 300 K (solid line). The dashed line in panel (a) indicates the DOS in the absence of electron–phonon coupling. The dotted lines in panels (a) and (b) indicate the calculation performed removing the local component of the electron-phonon coupling.
Visualization of the spread of the wavefunction initially localized by dynamic disorder.
The dashed lines represent the spread of the wavefunction in the x direction [ see Eq. (12)] for several starting wavefunctions. The solid line is the temperature averaged .
Temperature dependence of the three components of the mobility tensor.
A supercell with 4 rubrene molecules [replicated four times, compare with the schematics of Fig. 2(c)] used to study charge transport in the absence of correlation between the transfer integral fluctuations. The off-diagonal element between neighboring molecules is modulates by 6 different nuclear modes (indicated by the label on the segments) with similar electron-phonon coupling parameter.
(a) DOS (per molecule) and (b) energy resolved localization length of 2D model of rubrene in the presence of correlation between the fluctuation of the coupling (dashed line) and in the absence of correlation (solid line).
Parameters of the model Hamiltonian.
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