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Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
Theoretical estimation of the optical bandgap in a series of poly(aryl-ethynylene)s: a DFT study
José M Granadino-Roldán1, Andrés Garzón2, Mónica Moral1
1Departamento de Química Física y Analítica, Facultad de Ciencias Experimentales, Universidad de Jaén, Paraje las Lagunillas, s/n. 23071, Jaén, Spain.
Abstract:
Aimed to optimize the ratio accuracy/computational cost, in this work we study the performance of three different theoretical methodologies in the calculation of the optical bandgap for a test set made of a number of poly(aryl-ethynylene)s related polymers. Infinite, ideal polymer chains were first optimized by means of periodic calculations. Different length oligomers were afterward generated by direct replication of the corresponding periodic structure and their optical bandgaps were calculated by means of different time dependent-density functional theory (TD-DFT) methodologies. These results were fitted to an exponential function for each oligomer family in order to get a theoretical estimation of the optical bandgap for each polymer to be compared to the experimental reported values. The best result was obtained for TD-M06-2X yielding an average deviation of 3.4% with respect to the experimental values.
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