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arXiv · 1712.05620

Molecular Tuning of the Magnetic Response in Organic Semiconductors

Erik R. McNellis·Sam Schott·Henning Sirringhaus·Jairo Sinova
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Abstract

The tunability of high-mobility organic semi-conductors (OSCs) holds great promise for molecular spintronics. In this study, we show this extreme variability - and therefore potential tunability - of the molecular gyromagnetic coupling ("g-") tensor with respect to the geometric and electronic structure in a much studied class of OSCs. Composed of a structural theme of phenyl- and chalcogenophene (group XVI element containing, five-membered) rings and alkyl functional groups, this class forms the basis of several intensely studied high-mobility polymers and molecular OSCs. We show how in this class the g-tensor shifts, $\Delta g$, are determined by the effective molecular spin-orbit coupling (SOC), defined by the overlap of the atomic spin-density and the heavy atoms in the polymers. We explain the dramatic variations in SOC with molecular geometry, chemical composition, functionalization, and charge life-time using a first-principles theoretical model based on atomic spin populations. Our approach gives a guide to tuning the magnetic response of these OSCs by chemical synthesis.

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Erik R. McNellis, Sam Schott, Henning Sirringhaus, Jairo Sinova. 2017-12-15. Molecular Tuning of the Magnetic Response in Organic Semiconductors. https://doi.org/10.1103/physrevmaterials.2.074405

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