Occasionally, we interject a Molecule of the Month of our own at Imperial College. To start the New year off with some chemistry, have a look at http://www.ch.ic.ac.uk/motm/cavities.html where we present the 3D structure recently determined for the famous Diels-Alderase, the first protein to have been shown to catalyse a pericyclic cycloaddition reaction, and we also include the anthracene-resorcinol cavitand, which forms cavities (by virtue of a H-bonded network) of the right size to catalyse a Diels Alder addition. Please also note the vastly improved analytic features of Chime 2.0, which include inter alia, measurement of bond distances, angles, torsions, and much much more. Finally (since all this comes in fact from a lecture course on Pericyclic reactions) please note the fascinating orbitals for Mobius benzene; http://www.ch.ic.ac.uk/local/organic/pericyclic/mob.3dmf (for which you will need a 3DMF plugin such as Quick3D) which I use to illustrate antarafacial components. Dr Henry Rzepa, Dept. Chemistry, Imperial College, LONDON SW7 2AY; mailto:rzepa@ic.ac.uk; Tel (44) 171 594 5774; Fax: (44) 171 594 5804. URL: http://www.ch.ic.ac.uk/rzepa/ If my digital email signature is invalid, download a new root at http://www.belsign.be/en/services/receive/install-ca.html chemweb: A list for Chemical Applications of the Internet. To post to list: mailto:chemweb@ic.ac.uk Archived as: http://www.lists.ic.ac.uk/hypermail/chemweb/ To (un)subscribe, mailto:majordomo@ic.ac.uk the following message; (un)subscribe chemweb List coordinator, Henry Rzepa (mailto:rzepa@ic.ac.uk)