C60/Corannulene on Cu(110): A Surface-Supported Bistable Buckybowl−Buckyball Host−Guest System
journal contributionposted on 09.04.2008, 00:00 by Wende Xiao, Daniele Passerone, Pascal Ruffieux, Kamel Aït−Mansour, Oliver Gröning, Erio Tosatti, Jay S. Siegel, Roman Fasel
Corannulene (COR) buckybowls were proposed as near ideal hosts for fullerene C60, but direct complexation of C60 and COR has remained a challenge in supramolecular chemistry. We report the formation of surface-supported COR−C60 host−guest complexes by deposition of C60 onto a COR lattice on Cu(110). Variable-temperature scanning tunneling microscopy studies reveal two distinctly different states of C60 on the COR host lattice, with different binding energies and bowl−ball separations. The transition from a weakly bound precursor state to a strongly bound host−guest complex is found to be thermally activated. Simple model calculations show that this bistability originates from a subtle interplay between homo- and heteromolecular interactions.