Equilibrium solution coordination chemistry

On behalf of the Editorial Board, we are pleased to introduce this themed issue of New J. Chem. devoted to equilibrium solution coordination chemistry. Research on complexation equilibria (herein the term complex is used in its broadly accepted definition) embraces all areas of the chemical sciences. Knowledge of the fundamentals of how chemical thermodynamics and kinetics operate has a tremendous impact on research in other disciplines, such as biology, medicine, environmental sciences, mining and metal recycling/recovery by hydrometallurgical processes, waste management, agriculture, energy, engineering, instrumentation, etc. The study of chemical equilibria also plays a pivotal role in the design and synthesis of new chemical compounds, their characterization and the determination of their physicochemical properties, as well as their exploitation for specific applications. The relevance of this topic results from the simple assertion that many properties of elements and compounds depend mainly on their interactions in a given system. For example, the biological activity or the environmental impact of an element or molecule can most often be explained by a detailed study of these interactions, whose nature and strength can be evaluated by chemical equilibria and other thermodynamic studies. Speciation modelling based on chemical equilibrium data is commonly used to improve the performance of commercial products, investigate the mobility of pollutants and toxic wastes in the environment, optimize industrial processes, or explain the mechanisms of action of biologically active substances. Furthermore, advanced structural and thermodynamic solution studies yield deeper insights into the mechanisms of these interactions. Hence, the proposed selection of articles represents a wide variety of topics, including:

• Speciation, chemometrics and methodology.

• Solution equilibria and kinetics in relation to coordination chemistry, supramolecular chemistry, drug design, etc.

• Analytical methods and sensors based on metal complexes.

• Solution equilibria and industrial processes (e.g. hydrometallurgy, ion-exchange, catalysis, etc.)

• Nanostructured metal complexes.

• Metal complexes of environmental and biological interest (e.g. proteomics and metabolomics, interactions with metalloenzymes and biomolecules, etc.)

• Metals in health sciences (e.g. transport, homeostasis, toxicity, therapy, diagnosis and imaging, etc.)

In homage to the founding fathers, who established the fundamental concepts of equilibrium solution coordination chemistry a century ago, and to their inspired followers, some of whom became our mentors, this themed issue seeks to highlight the latest advances in the field. With more than 80 contributions from all over the world, this special issue is a showcase of the creativity and vitality of solution chemists with various backgrounds and centers of interest. More than half of the papers are co-authored by scientists who attended the International Symposium on Metal Complexes (ISMEC 2017 – https://ismec2017.sciencesconf.org) held on June 11–15, 2017 in Dijon, France. Since 1974, it has been the sole annual conference devoted to the solution equilibrium chemistry and thermodynamics of complexes. This uninterrupted series of annual meetings, launched by the “Gruppo di Termodinamica dei Complessi” (GTC – http://www.gtc2014.com), began in 1974 in Firenze, which will also host the 45th edition on June 3–7, 2018. In recent years, previous ISMEC conferences were held in Bilbao (2010), Taormina (2011), Lisbon (2012), Burgos (2013), Pavia (2014), Wroclaw (2015), and Barcelona (2016). The historical city of Dijon, a landmark for medieval, renaissance and classical architecture (the picture on the front cover provides a taste of it), but also for gastronomy, fine wines, and the so-called “French art de vivre”, hosted the 44th meeting in 2017 (Fig. 1). Nearly 170 delegates from both academia and industry, including Nobel Laureate Prof. Jean-Pierre Sauvage, represented 20 different countries from 4 continents. The scientific program comprised altogether 5 plenary and 10 keynote lectures, 43 oral communications, and 86 posters. The open access proceedings of the meeting have been published in volume 7 of Acta of the International Symposia on Metal Complexes (ISSN: 2239-2459), available from the GTC web page and the HAL repository of scholarly documents (https://hal.archives-ouvertes.fr/).

Fig. 1 Members of the local organizing committee of the ISMEC 2017 conference. The picture was taken on June 14, 2017 during the gala dinner offered to the 170 delegates in the vaulted reception room of the Bastion des Hospices de Beaune (Côte d'Or, France), a XV^th century fortress decorated by 11 Aubusson tapestries woven between the XVII^th and XVIII^th centuries. From the left to the right: Claude Gros (guest co-editor), Ewen Bodio, Jean-Claude Chambron, Michel Meyer (Chair and guest editor), Thierry Belloir, Stéphane Brandès, Michael Knorr, the late Alain Tabard, Dominique Lucas, Nicolas Desbois, Claire Lejault, Charles Devillers, Sylvie Girardon, Mathieu Berthelot, Julie Echaubard, Léa Radal, Sophie Dal Molin-Fournier, Coline Canovas, Audrey Trommenschlager, Stéphanie Robin, Morgane Monney, Tamas Fodor, and Stéphanie Bis. Other members not appearing were Julie Bourdenet, Franck Denat, Claudine Filiatre, Laurent Plasseraud (guest co-editor), and Valentin Quesneau who took the picture. Thanks to all of them!

This themed issue appears as a timely collective volume, which brings together not only manuscripts from key contributors to the various topics discussed during this conference, but also papers written by renowned colleagues upon invitation, along with a few articles taken from the spontaneous submissions to New J. Chem. that fit within these themes. The full list of articles appearing in this issue can be consulted on the journal home page (www.rsc.org/njc), under the Themed Collections tab. We hope that this selection of focus articles, perspectives, and regular research papers will be useful learning guides for newcomers or refreshers for those already working in the area.

The Guest Editors gratefully acknowledge the Royal Society of Chemistry and the Centre National de la Recherche Scientifique for the publication of this themed issue. Furthermore, we would like to thank the Editor-in-Chief, the Associate Editors, and all the members of the publishing office in Cambridge, with a special mention to Dr Caroline Knapp, for efficient handling of the manuscripts, including the intense reviewing process that guarantees the quality of the accepted papers. Nearly 90 submissions were handled in the usual way with international and independent peer review. We are in debt to the numerous volunteer referees and, of course, to all the invited authors for their contributions.

Enjoy this themed issue!

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