French–Nordic relations have long been characterized by deep mutual admiration, wide-ranging cultural exchange, and collaboration in the scientific-technological arena. The nations in question dedicate substantial amounts of funds annually to international collaboration and to French–Nordic collaboration in particular. Both France and the Nordic countries are home to unique large-scale facilities such as the ESRF and MAXLAB, historic and legendary universities, as well as world-class research groups at smaller universities in spectacular settings. The world’s northernmost university UiT—The Arctic University of Norway at 70° N, home base of one of the guest editors (in Tromsø), is an example of the latter. This Special Issue of Comptes Rendus Chimie celebrates French–Nordic collaboration in coordination chemistry and materials chemistry and/or research groups interested or engaged in such collaboration.

Herein, Piligkos et al. (doi:10.5802/crchim.282) describe the influence of long aliphatic side chains on the magnetic properties of tris(salen)-type lanthanide (Tb-Tm and Y) complexes.

Cattey and Plasseraud (doi:10.5802/crchim.260) investigate the reactivity of the hydroxo di-n-butyltin-trifluoromethanesulfonato dimer complex towards 1,10-phenanthroline leading to novel 1,10-phenanthroline-complexed, mono- and binuclear organotin(IV) derivatives.

Henrichsen, Bendix, and Weihe (doi:10.5802/ crchim.266) present and interpret the parallel-mode X-band EPR spectra of the hexaaquamanganese(II) ion, assisted by the species’ exact T_d (tetrahedral) crystallographic symmetry.

Abou-Fayssal, Poli, Philippot, Riisager, and Manoury (doi:10.5802/crchim.301) review polymeric nanoreactors for catalytic applications, including a recent nanoreactor used in biphasic catalysis.

Pascal, Zaborova, and Siri (doi:10.5802/crchim. 292) report the synthesis and characterization of two nickel complexes based on 1,2,4-triamino-5-nitrobenzene as air-stable aromatic polyamines, highlighting the importance of intramolecular hydrogen-bonding interactions and the influence of the nitro group on the stability of the complexes.

Devillers and coworkers (doi:10.5802/crchim.307) describe a synthesis of meso-(pyridin-2-ylmethyl)porphyrins based on the nucleophilic attack by (pyridin-2-ylmethyl)lithium on a porphyrin with one free meso-position.

Lioret and Decréau (doi:10.5802/crchim.335) present a proof of concept of a novel approach to in vivo imaging involving Cherenkov Radiation Energy Transfer (CRET) from ¹⁸F-fluorodeoxyglucose to subphthalocyanine fluorophores.

Using relativistic DFT calculations, Ghosh and Conradie (doi:10.5802/crchim.264) shed new light on gold(II) porphyrins, rare mononuclear Au(II) species that were isolated and structurally characterized only a few years ago. A key feature of these complexes is a wave deformation of the porphyrin, a reflection of a noninnocent porphyrin macrocycle.

Also focusing on gold complexes, Orthaber et al. (doi:10.5802/crchim.328) describe the use of the semi-rigid cis-1,2-bis(diphenylphosphino)ethene ligand, which favors the formation of mononuclear, as opposed to binuclear, Au(I) complexes.

Finally, guest editors Ghosh and Gros and their coworkers (doi:10.5802/crchim.299) introduce hypsochlorins, named by analogy with hypsoporphyrins, which exhibit blue-shifted optical spectra relative to their normal counterparts.

It is worth mentioning that this special issue is being published shortly after the 1st Åsgard Horizon French-Norwegian Inorganic and Materials Chemistry Symposium, which took place May 30–31, 2024, in Dijon, France. The second edition of this symposium will be held in Tromsø, Norway, in June, 2025. Both events were organized under the auspices of the Institut Français de Norvège, whose support we deeply appreciate.

We are also grateful to the French Académie des Sciences and to Dr Pierre Braunstein, Editor-in-Chief of the Comptes Rendus Chimie, as well as to Mr. Julien Desmarets for his efficient handling of the submitted manuscripts. We trust that this issue will encourage many others, from exchange students to senior scientists, to take advantage of the wide-ranging opportunities afforded by French–Nordic collaboration.