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Two types of the metallofullerene Nd@C82 have been isolated and characterized. HPLC was used to isolate Nd@C82(I, II). The two isomers were characterized by mass spectrometry and UV-Vis-N1R absorption spectroscopy. Nd@C82(I) was found to be similar in structure to the main isomer of other lanthanofullerenes such as La@C82. We assign Nd@C82(I) to have a C2v cage symmetry. Nd@C 82(II) showed a markedly different UV-Vis-NIR absorption spectrum to Nd@C82(I). Its spectrum is in good agreement with that of the minor isomer of metallofullerenes such as Pr@C82. We therefore assign Nd@C82(II) to have a Cs cage symmetry. In contrast to other metallofullerenes, both isomers appear to be equally abundant. Their molecular orbital structures have been studied by a combination of scanning tunnelling microscopy (STM) and density functional theory (DFT). Matching filled and empty-states STM images to DFT calculations allowed us to distinguish directly between the two isomers on a substrate. copyright The Electrochemical Society.

We have investigated self-assembled island formation, molecular detail and interesting contrast reversal effects for Er3N@C80 and Sc3N@C80 on Au(111) and Ag/Si(111) surfaces using variable temperature scanning tunnelling microscopy (STM) and spectroscopy (STS). The trinitride containing fullerenes have been evaporated onto Ag-passivated Si(111) at room temperature and self-assembled into close-packed 2-D islands. Gentle annealing at 200 - 300 °C is required for the formation of close-packed islands with 20 - 50 nm diameter on the Au(111) surface. Variable-voltage STM reveals bias-dependent contrast anomalies within the islands, and at low temperatures (< 90K), intra-molecular resolution of the fullerenes has been achieved. STS measurements indicate that the bright/dark anomalies may be caused by different electron densities of states for the "normal" and "anomalous" fullerenes. ©2008 IOP Publishing Ltd.

Trimetallic nitride template fullerenes have been deposited onto a variety of substrates in order to elucidate the substrate-fullerene interactions. We have investigated self-assembled island formation and molecular detail of Er3N@C80 and Sc3N@C80 on Ag/Si(1 1 1), Au(1 1 1)/mica, Si(1 1 1), and Si(0 0 1) using variable temperature scanning tunnelling microscopy (STM). At room temperature, the fullerenes self-assemble into monolayer-high hexagonal close-packed islands on Ag-passivated Si(1 1 1) whereas annealing at elevated temperatures (250-300 °C) is necessary for the self-assembly of close-packed islands on Au(1 1 1). Intra-molecular resolution of the fullerenes has been achieved at liquid nitrogen temperature on Ag/Si(1 1 1) and already at room temperature on Si(0 0 1), when the rotation of the fullerenes is frozen. Whereas the bonding between the fullerenes and Si surfaces is mainly covalent, it appears to be mainly van-der-Waals on the other surfaces. © 2006 Elsevier B.V. All rights reserved.

Molecular structures appear to be natural candidates for a quantum technology: individual atoms can support quantum superpositions for long periods, and such atoms can in principle be embedded in a permanent molecular scaffolding to form an array. This would be true nanotechnology, with dimensions of order of a nanometre. However, the challenges of realising such a vision are immense. One must identify a suitable elementary unit and demonstrate its merits for qubit storage and manipulation, including input / output. These units must then be formed into large arrays corresponding to an functional quantum architecture, including a mechanism for gate operations. Here we report our efforts, both experimental and theoretical, to create such a technology based on endohedral fullerenes or 'buckyballs'. We describe our successes with respect to these criteria, along with the obstacles we are currently facing and the questions that remain to be addressed., 20 pages, 13 figs, single column format