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arXiv · 1503.07246

Energy Pooling Upconversion in Organic Molecular Systems

M. LaCount·D. Weingarten·N. Hu·S. Shaheen·J. van de Lagemaat·G. Rumbles·D. Walba·M. T. Lusk
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Abstract

A combination of molecular quantum electrodynamics, perturbation theory, and ab initio calculations was used to create a computational methodology capable of estimating the rate of 3-body singlet upconversion in organic molecular assemblies. The approach was applied to quantify the conditions under which such relaxation rates, known as energy pooling, become meaningful for two test systems: stilbene-fluorescein and hexabenzocoronene-oligothiophene. Both exhibit low intra-molecular conversion but inter-molecular configurations exist in which pooling efficiency is at least 90\% when placed in competition with more conventional relaxation pathways. For stilbene-fluorescein, the results are consistent with data generated in an earlier experimental investigation. Exercising these model systems facilitated the development of a set of design rules for the optimization of energy pooling.

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M. LaCount, D. Weingarten, N. Hu, S. Shaheen, J. van de Lagemaat, G. Rumbles, D. Walba, M. T. Lusk. 2015-03-25. Energy Pooling Upconversion in Organic Molecular Systems. https://doi.org/10.1021/acs.jpca.5b00509

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