Parametrization of Extended Gaussian Disorder Models from Microscopic Charge Transport Simulations

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• 作者：Pascal Kordt ; Ole Stenzel ; Bj枚rn Baumeier ; Volker Schmidt ; Denis Andrienko
• 刊名：Journal of Chemical Theory and Computation
• 出版年：2014
• 出版时间：June 10, 2014
• 年：2014
• 卷：10
• 期：6
• 页码：2508-2513
• 全文大小：372K
• 年卷期：v.10,no.6(June 10, 2014)
• ISSN：1549-9626

文摘

Simulations of organic semiconducting devices using drift-diffusion equations are vital for the understanding of their functionality as well as for the optimization of their performance. Input parameters for these equations are usually determined from experiments and do not provide a direct link to the chemical structures and material morphology. Here we demonstrate how such a parametrization can be performed by using atomic-scale (microscopic) simulations. To do this, a stochastic network model, parametrized on atomistic simulations, is used to tabulate charge mobility in a wide density range. After accounting for finite-size effects at small charge densities, the data is fitted to the uncorrelated and correlated extended Gaussian disorder models. Surprisingly, the uncorrelated model reproduces the results of microscopic simulations better than the correlated one, compensating for spatial correlations present in a microscopic system by a large lattice constant. The proposed method retains the link to the material morphology and the underlying chemistry and can be used to formulate structure鈥損roperty relationships or optimize devices prior to compound synthesis.