Preface

Abstract
ISCOM'2003, the fifth venue of a series of successful Symposia, was mainly supported by the Région des Pays de la Loire; with complementary funding from the Chemistry and the Physics Departments of the Centre National de la Recherche Scientifique (CNRS), the Délégation Générale à l'Armement, the Ministère Délégué a la Recherche et aux Nouvelles Technologies and the University of Angers. We are very grateful to these funding agencies, especially as the sponsorship has allowed for many young researchers (below 35) to attend the Conference.

The Symposium brought together chemists and physicists concerned with the latest developments in the synthesis, crystal growth, molecular crystal structure and electronic structure, phase transitions and electronic properties of low dimensional crystalline molecular materials, molecular metals and superconductors, and the theoretical aspects of these systems of strongly correlated electrons for advanced technologies. 240 participants from Japan (86), France (35), USA (18), Russia (17), UK (14), Spain (14), Germany (12), Canada (7), Italy (7), Portugal (7), Croatia (4), Danemark (4), Switzerland (4), Australia (3), Korea (3), Poland (3), The Netherlands (2), China (1), Finland (1), and Greece (1) - the two youngest of whom were a Japanese and an Australian PhD students - stay in residence from the evening of Sunday 21st September to Friday 26th September 2003 at the hotel "Les Jardins de l'Atlantique", in Talmont-Saint Hilaire (Vendée, France). It should be noted that 50% of the participants were younger than 35 - of whom 51 were PhD students (that is, 20% of the total number of participants). These rather impressive. figures are seen as significant of the spirit or a multidisciplinary domain whose biannual high level international Symposium, also serves as an exceptional venue for the training of young researchers in the field. Given - and despite this overwhelming response and the eagerness of the participants to contribute oral presentations - we have decided to keep with as many 20 minutes talks as possible and had to resolve - rather reluctantly to run parallel sessions on Wednesday and Thursday mornings. Yet, in the end, there has been a significant number of solicitations for oral contributions of great interest which were simply impossible to fit in the schedule. We thank all the colleagues who have submitted their exciting work and who have presented their oral and posters contributions during the 23 sessions of the Symposium.

Seven sessions were devoted to materials chemistry, of which two sessions dealt more specifically with organic synthesis and two sessions with molecular magnetic materials. The experimental aspects of one- and two-dimensional physics were discussed in two and four sessions, respectively. Aside several theoretical talks interspersed within the former experimental sessions, two sessions were dedicated to theoretical aspects of strongly correlated electron systems in low dimension. One session focused on high magnetic field phenomena and two sessions covered charge ordering phenomena. Finally, upcoming issues related to surface and interface phenomena in molecular conductors were addressed in one session.

The current research in chemistry of molecular precursor is dominated by the concepts of multifunctional systems constructed on tetrathiafulvalene-based redox cores equipped with hydrogen-bond donor-acceptor functionalities or tetrathiafulvalene-based ligands capable of coordinating a metal center. Likewise, in the same spirit, the introduction of chiral functionalities is reported in several contributions. Aside those in the chemistry of stabilized polyacenes and the chemistry of molecular inorganic macrospins species: most of the creative developments continue to involve the TTF platform. In that context, crystal engineering concepts associated with the manipulation of hydrogen bonds and complementary weak intermolecular interactions in competition with overlap interactions between frontier orbitals of the precursors is today a very active field of research reaching out in field of molecular magnetic materials. Also, the materials chemistry of single component molecular metals and the development of strategies for the chemical control of band filling in molecular metals are areas of intense research. Considerable progress reported in first principle-based electronic structure calculations for large complex systems and band structure calculations of molecular metals should diffuse promptly in the molecular materials community.

On the physics side, recent advances in understanding the localization-delocalization-charge ordering competition in low dimensional systems of strongly correlated electrons, and their formulation at ISCOM'03 in a language and format accessible to experimentalists and materials scientists, carries a great many promises for significant developments in the conception of novel molecular superconductors. The physics of one- and two-dimensional molecular metals and superconductors was a strong component of ISCOM'03 with very diverse complementary experimental approaches including transport, uniaxial and isotropie high pressures and high magnetic fields studies, thermal conductivity, STM. Two dimensional conductors have proved to be prototype materials for the study of interacting electron gases through the phenomenon of Mott localization exhibited in some BEDT-TTF salts. Applications of angle-resolved photo-emission investigations have been reported and emerge as a very promising area for future developments. Coupled to quantum chemistry calculations the latter carry along an enormous potential, as exemplified by the wealth of information delivered on the nature of the chemical bonding and electronic structure of molecular solids. The reports of superconductivity induced by a large magnetic field in RETS salts containing magnetic anions have shown how organic materials have brought the experimental proof for a theory which was proposed several decades ago.

For the past two decades, the field of low dimensional molecular materials has developed a rather singular, integrated culture where organic and inorganic chemists, materials scientists, quantum chemists, joined forces with condensed matter physicists: experimentalists and theoreticians a like, shared concepts and cut across disciplinary barriers in a symbiosis which was there plain to see at ISCOM'03. The international committee has decided that ISCOM'2005 will be organized by Jim Brooks (Tallahassee, Florida, USA) who will lead a joint effort of the High Magnetic Fields Laboratories and the American community in the field.

Patrick Batail

Chairman, ISCOM'2003

E. Canadell, N. Dupuis, M. Fourmigué, D. Jérome and J.-P. Pouget

Co-chairmen and editors of the ISCOM'2003 proceedings