Letters to Nature

Nature 394, 758-760 (20 August 1998) | doi:10.1038/29487; Received 20 April 1998; Accepted 8 June 1998

Archetypal energy landscapes

David J. Wales1, Mark A. Miller1 & Tiffany R. Walsh1

  1. University Chemical Laboratories, Lensfield Road, Cambridge CB2 1EW, UK

Correspondence to: David J. Wales1 Correspondence and requests for materials should be addressed to D.J.W. (e-mail: Email: dw34@cus.cam.ac.uk).

Energy landscapes hold the key to understanding a wide range of molecular phenomena. The problem of how a denatured protein re-folds to its active state (Levinthal's parado1) has been addressed in terms of the underlying energy landscape2, 3, 4, 5, 6, 7, as has the widely used 'strong' and 'fragile' classification of liquids8,9. Here we show how three archetypal energy landscapes for clusters of atoms or molecules can be characterized in terms of the disconnectivity graphs10 of their energy minima—that is, in terms of the pathways that connect minima at different threshold energies. First we consider a cluster of 38 Lennard–Jones particles, whose energy landscape is a 'double funnel' on which relaxation to the global minimum is diverted into a set of competing structures. Then we characterize the energy landscape associated with the annealing of C60 cages to buckministerfullerene, and show that it provides experimentally accessible clues to the relaxation pathway. Finally we show a very different landscape morphology, that of a model water cluster (H2O)20, and show how it exhibits features expected for a 'strong' liquid. These three examples do not exhaust the possibilities, and might constitute substructures of still more complex landscapes.