Redox-controlled potassium intercalation into two polyaromatic hydrocarbon solids

Romero, F. D. et al. (2017) Redox-controlled potassium intercalation into two polyaromatic hydrocarbon solids. Nature Chemistry, 9(7), pp. 644-652. (doi: 10.1038/nchem.2765)

Abstract

Alkali metal intercalation into polyaromatic hydrocarbons (PAHs) has been studied intensely after reports of superconductivity in a number of potassium- and rubidium-intercalated materials. There are, however, no reported crystal structures to inform our understanding of the chemistry and physics because of the complex reactivity of PAHs with strong reducing agents at high temperature. Here we present the synthesis of crystalline K2Pentacene and K2Picene by a solid–solid insertion protocol that uses potassium hydride as a redox-controlled reducing agent to access the PAH dianions, and so enables the determination of their crystal structures. In both cases, the inserted cations expand the parent herringbone packings by reorienting the molecular anions to create multiple potassium sites within initially dense molecular layers, and thus interact with the PAH anion π systems. The synthetic and crystal chemistry of alkali metal intercalation into PAHs differs from that into fullerenes and graphite, in which the cation sites are pre-defined by the host structure.

• Item Type: Articles
• Additional Information: We acknowledge financial support from the UK Engineering and Physical Sciences Research Council (EP/K027255 and EP/K027212), the European Union/JST SICORP-LEMSUPER FP7-NMP-2011-EU-Japan project (contract no. NMP3-SL-2011- 283214), the Mitsubishi Foundation, the Japan Society for the Promotion of Science under the Scientific Research on Innovative Areas ‘J-Physics’ Project (no. 15H05882), the ‘World Premier International (WPI) Research Center Initiative for Atoms, Molecules and Materials,’ the Ministry of Education, Culture, Sports, Science, and Technology of Japan and the Japan Science and Technology Agency under the ERATO Isobe Degenerate π-Integration Project.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Ganin, Dr Alexey
• Authors: Romero, F. D., Pitcher, M.J., Hiley, C.I., Whitehead, G.F.S., Kar, S., Ganin, A.Y., Antypov, D., Collins, C., Dyer, M.S., Klupp, G., Colman, R.H., Prassides, K., and Rosseinsky, M.J.
• Subjects: Q Science > QC Physics; Q Science > QD Chemistry
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Nature Chemistry
• Publisher: Nature Publishing Group
• ISSN: 1755-4330
• ISSN (Online): 1755-4349
• Published Online: 24 April 2017
• Copyright Holders: Copyright © 2017 Macmillan Publishers Limited, part of Springer Nature
• First Published: First published in Nature Chemistry 9(7):644-652
• Publisher Policy: Reproduced in accordance with the publisher copyright policy