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Comprehensive Summary: Three heteronuclear IrIII‐CoII arrays, [Co(H2O)6]2[Ir(ppyCOO)(ppyCOOH)(bpy)]2[Ir(ppyCOO)2(bpy)]2(NO3)2⋅10.5H2O (2), [Co(H2O)6]{Co(H2O)4[Ir(ppyCOO)2(bpy)]2}[Ir(ppyCOO)2(bpy)]2⋅15H2O (3) and {Co(H2O)2[Ir(ppyCOO)2(bpy)]2}⋅2CH3OH⋅3H2O (4), have been synthesized by combining paramagnetic CoII ion with luminescent IrIII‐metalloligand, [Ir(ppyCOOH)2(bpy)][Ir(ppyCOO)2(bpy)]⋅5H2O (1), where ppyCOOH = 3‐(pyridin‐2‐yl)benzoic acid and bpy = 2,2'‐bipyridyl. Owing to the variable charged states of compound 1 at different pH, compounds 2 and 3 are discrete ionic complexes containing hydrated Co2+ cations and deprotonated [Ir(ppyCOO)2(bpy)]– anions as well as coexisting neutral [Ir(ppyCOO)(ppyCOOH)(bpy)] (for 2) or Co(H2O)4[Ir(ppyCOO)2(bpy)]2 trinuclear molecule (for 3). Whereas compound 4 consists of self‐assembled two‐dimensional coordination polymer with Co‐metalloligand dative bonds. The hexa‐coordinated CoII cores in all complexes display octahedral geometries with varying degrees of distortion. In a bias dc field, the ac susceptibilities for 2—4 reveal slow magnetic relaxation. Moreover, the solid‐state phosphorescence is observed for compounds 2 and 3 due to weak supramolecular interaction between CoII ion and Ir‐moiety but is severely quenched for 4, where the Co center is strongly connected to the metalloligand. To the best of our knowledge, this is the first report of Ir‐Co systems showing both slow magnetization relaxation and photoluminescence. [ABSTRACT FROM AUTHOR]

The structural transformations of metal nanoclusters are typically quite complex processes involving the formation and breakage of several bonds, and thus are challenging to study. Herein, we report a case where two lacunary Keggin polyoxometallate templated silver single-pods [PW9O34@Ag51] (SD/Ag51b) fuse to a double-pod [(PW9O34)2@Ag72] by reacting with 4,4'-bipyridine (bipy) or 1,4-bis(4-pyridinylmethyl)piperazine (pi-bipy). Their crystal structures reveal the formation of a 2D 44-sql layer (SD/Ag72a) with bipy and a 3D pcu framework (SD/Ag72c) with pi-bipy. The PW9O349− retains its structure during the cluster fusion and cluster-based network formation. Although the two processes, stripping of an Ag-ligands interface followed by fusion, and polymerization, are difficult to envisage, electrospray ionization mass spectrometry provides enough evidences for such a proposal to be made. Through this example, we expect the structural transformation to become a powerful method for synthesizing silver nanoclusters and their infinite networks, and to evolve from trial-and-error to rational. Controlling the structural transformations of metal clusters is challenging. Here, the authors synthesize a silver nanocluster and study the structural changes that take place upon reaction with bipyridine derivatives. [ABSTRACT FROM AUTHOR]

The hydrothermal synthesis of the hydrogenated and deuterated analogous of lindgrenite, their thermal and optical properties, and magnetic properties as a function of temperature and field are presented. The results have pointed to a ferrimagnetic ground state below 13 K without any sign of geometrical frustration.

The nuclear, magnetic properties and heat capacity of the layered ferromagnet Co5(OH)6(SO4)2(H2O)4 are reported. The results point to the presence of near-neighbor ferromagnetic coupling within the layers, resulting in long-range ordering only within the layer, while the interlayer cobalt atom has a randomly oriented moment.

The synthesis, crystal structure, and electrical, optical, and magnetic properties of k-BETS2[Fe(super III)(C2O4)CI2] where BETS is bis(ethylenedithio)tetraselenafulvalene, are reported. It is an organic-inorganic hybrid that displays the coexistence of two-dimensional (2D) pi electrons, 1D antiferromagnetism, and possible canted antiferromagnetism involving pi and d spins.

Research describes the synthesis of three cobalt(II)-pyromellitate complexes, purple, red, and pink, which exhibit hydrogen-bonded and coordination-bonded structures. The magnetic properties of purple complex consists of three ground states and two types of hysteresis loops. Data indicate that the red and pink complexes are paramagnets.

The synthesis and characterization of two members of a family of porous magnetic materials and the interactions between the pillaring agent and the compositionally complex inorganic layer are described. The magnetism of the pillared layered cobalt hydroxides is complex due to the influences of multiple metal sites, inter- and intralayer exchange, spin-orbit coupling and geometrical frustration, and the controlling influence of the rigidity of the organic pillar on the chemistry and its influence on the cooperative magnetism are shown.