THE ROYAL SOCIETY OF CHEMISTRY Journal of Materials Chemistry Scientific Editor Staff Editor Professor Anthony R. West Mrs. Janet M. Leader Department of Chemistry The Royal Society of Chemistry University of Aberdeen Thomas Graham House Meston Walk Science Park Aberdeen AB9 2UE, UK Cambridge CB4 4WF, UK Assistant Editor: Mrs. F. J. O'Carroll Editorial Secretary: Miss D. J. Halls Graphics Designer: Ms. C. Taylor- Reid Materials Chemistry Editorial Board Anthony R. West (Aberdeen) (Chairman) Peter G. Bruce (St. Andrews) H. Monty Frey (Reading) C. Richard A. Catlow (London) John W. Goodby (Hull) David A. Dunmur (Sheffield) Brian J. Tighe (Aston) Jean Etourneau (Bordeaux) Allan E. Underhill (Bangor) Wendy R. Flavell (UMIST) John D.Wright (Canterbury) ~~~~~~~~ ~ ~ ~ ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~~~~~ Internationa I Advisory Ed itoria I Board M. A. Alario-Franco (Madrid, Spain) A. J. Leadbetter (Daresbury, UK) K. Bechgaard (Copenhagen, Denmark) J. S. Miller (Wilmington, DE, USA) J. D. Birchall (Runcorn, UK) P. S. Nicholson (Hamilton, Canada) D. Bloor (Durham, UK) M. Nygren (Stockholm, Sweden) A. K. Cheetham (Santa Barbara, USA) V. Percec (Cleveland, OH, USA) E. Chiellini (Pisa, Italy) N. Plate (Moscow, Russia) P. Day (London, UK) C. N. R. Rao (Bangalore, India) B. Dunn (Los Angeles, USA) M. Ratner (Evanston, IL, USA) W. J. Feast (Durham, UK) J. Rouxel (Nantes, France) A. Fukuda (Tokyo, Japan) R. Roy (University Park, PA, USA) D. Gatteschi (Florence, Italy) J.L. Serrano (Zaragoza, Spain) J. B. Goodenough (Austin, TX, USA) J. N. Sherwood (Glasgow, UK) A. C. Griffin (Hattiesburg, USA) J. Simon (Paris, France) S-i. Hirano (Nagoya, Japan) J. F. Stoddart (Birmingham, UK) P. Hodge (Manchester, UK) S. Takahashi (Osaka, Japan) H. lnokuchi (Okazaki, Japan) G. J. T. Tiddy (Bebington and Salford, W. Jeitschko (Munster, Germany) UK) 0. Kahn (Orsay, France) Yu. D. Tretyakov (Moscow, Russia) M. Lahav (Rehovot, Israel) J. W. White (Canberra, Australia) R. Xu (Changchun, China) Journal of Materials Chemistry (ISSN 9959-9428) is published monthly by The Royal Society of Chemistry, Thomas Graham House, Science Park, Milton Road, Cambridge CB4 4WF, UK. All orders accompanied with payment should be sent directly to The Royal Society of Chemistry, Turpin Distribution Services Ltd., Blackhorse Road, Letchworth, Herts SG6 1 HN, UK.NB Turpin Distribution Services Ltd., distributors, is wholly owned by The Royal Society of Chemistry. 1994 Annual subscription rate EC (inc. UK) f381.00, USA $718.00, Canada €431 .OO (plus GST), Rest of World f410.00. Customers should make payments by cheque in sterling payable on a UK clearing bank or in US dollars payable on a US clearing bank. Air freight and mailing in the USA by Publications Expediting Inc., 200 Meacham Avenue, Elmont, NY 11003. USA POSTMASTER: send address changes to Journal of Materials Chemistrx Publications Expediting Inc., 200 Meacham Avenue, Elmont, NY 11003. Second Class postage paid at Jamaica, NY 11 431.All other dispatches outside the UK by Bulk Airmail within Europe, Accelerated Surface Post outside Europe. PRINTED IN THE UK. @ The Royal Society of Chemistry, 1994. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form, or by any means, electronic, mechanical, photographic, recording, or otherwise, without the prior permission of the publishers. Professor A. R. West, Scientific Editor Mrs. J. M. Leader, Staff Editor Tel.: Aberdeen (0224) 27291 8 Tel.: Cambridge (0223) 420066 Fax: (0224) 272938 E-Mail (INTERNET): Telex: 73458 UNIABN G RSCl @RSC.ORG Fax: (0223) 420247 or 423623 Telex: 818293 ROYAL G Advertisement sales: Tel. + 44 (0)71-287 3091; Fax +44 (0)71-494 11 34 INFORMATION FOR AUTHORS The Royal Society of Chemistry welcomes submission of manuscripts intended for pub- lication in two forms, Articles and Materials Chemistry Communications.These should describe original work of high quality dealing with the synthesis, structures, properties and applications of materials, particularly those associated with advanced technology. Articles Full papers contain original scientific work that has not been published previously. How- ever, work that has appeared in print in a short form such as a Materials Chemistry Com- munication is normally acceptable. Four copies of Articles including a top copy with figures etc. should be sent to The Editor, Journal of Materials Chemistry, The Royal Society of Chemistry, Thomas Graham House, Science Park, Milton Road, Cambridge CB44WF.UK. Materials Chemistry Communications Materials Chemistry Communications contain novel scientific work in short form and of such importance that rapid publication is war-ranted. The total length is rigorously restric- ted to two pages of the double-column A4 format. The manuscript will be returned for reduction if this length is exceeded. For a Communication consisting entirely of text and ten references, with no figures, equations or tables, this corresponds to approximately 1600 words plus an abstract of up to 40 words. Submission of a Materials Chemistry Com- munication can be made either to The Editor, Journal of Materials Chemistry, The Royal Society of Chemistry, Thomas Graham House, Science Park, Milton Road, Cambridge CB4 4WF, UK, or via a member of the Inter- national Advisory Editorial Board.In the latter case, the top copy of the manuscript includ- ing any figures etc., together with the name of the person to whom the Communication is being submitted, should be sent simul-taneously to the Editor at the Cambridge address. Authors may wish to contact the Board member to ensure that he is available to arrange review of the manuscript within reasonable time. In order to avoid delay in publication, proofs of Communications are not sent to authors unless this is specifically requested. Full details of the form of manuscripts for Articles and Materials Chemistry Communi- cations, conditions for acceptance etc. are given in issue number one of Journal of Materials Chemistry published in January of each year, or may be obtained from the Staff Editor. There is no page charge for papers published, in Journal of Materials Chemistry. Fifty reprints are supplied free of charge. Any author who is publishing in Journal of Materials Chemistry is entitled to a free copy of the issue in which the paper appears.