A series of novel three-dimensional (3-D) lanthanide-organic frameworks (LnOFs), with the general formula [Ln 2 (H-L) 3 (H 2 O) 4 ] ¥ (Ln = Dy III for 1, Gd III for 2, Tb III for 3, Eu III for 4, and Ho III for 5; H-L = N-protonated 2,6dihydroxypyridine-4-carboxylate), have been synthesized under hydrothermal conditions. X-ray structural analysis reveals that complexes 1-5 are isostructural and show the unique 3-D coordination framework with a trinodal (3,4,5)-connected (4.6 2 )(4 2 .6)(4 2 .8 4 )(4 3 .6.8 6 )(4 2 .6 5 .8 3 ) net topology, in which the H-L ligands adopt different μ 4 -and μ 3 -bridging forms. Variable-temperature magnetic susceptibility studies reveal that complexes 1-3 and 5 show ferromagnetic behaviors. Notably, complex 1 (Dy III ) is the first instance leading to ferromagnetic coupling for a lanthanide ion through a spin-polarization mechanism. The alternating current (ac) signal observed for 1 and 5 should originate from the long-range ferromagnetic ordering, or it could reflect the splitting of the J multiplet for Dy III or Ho III under a low symmetry crystal field, which would give rise to slow relaxation of the magnetization. Additionally, thermal stability of these crystalline materials has also been investigated by thermogravimetric analysis of mass loss.

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Two new CdII complexes formulated as {[Cd3(L)4](H2O)(CH3OH)3(Hdmpy)2}∞ (1) and {[Cd2(L)2(phen)2(H2O)2]}∞ (2) were prepared by a slow diffusion method from mixtures of 2,2′‐dithiodibenzoic acid (H2L) and Cd(ClO4)2·6H2O in the presence or absence of auxiliary phen ligand (L = 2,2′‐dithiodibenzoate, Hdmpy = protonated 2,6‐dimethylpyridine, and phen = 1,10‐phenanthroline). Their structures were determined by single‐crystal X‐ray diffraction technique. Complex 1 possesses a three‐dimensional (3D) α‐Po‐related framework containing [Cd3(L)4]2– cluster units as secondary building block, with a 41263 topology symbol. Complex 2 takes a one‐dimensional (1D) helical chain structure that is further assembled into a two‐dimensional (2D) network by the co‐effects of the inter‐chain O–H···O and C–H···O hydrogen bonds as well as π···π stacking interactions. Complexes 1 and 2 are both photoluminescent active materials, and their emission properties are closely related to their intrinsic structure arrangements.

To explore the coordination possibilities of perylene-based ligands with a larger conjugated π-system, four ZnII, MnII, and CoII coordination polymers with perylene-3,4,9,10-tetracarboxylate (ptc) and the chelating 1,10-phenanthroline (phen) ligands were synthesized and characterized: {[Zn2(ptc)(phen)2](H2O)10}∞ (1), {[Zn3(ptc)(OH)2(phen)2](H2O)3}∞ (2), {[Mn(ptc)0.5(phen)(H2O)2](H2O)1.5}∞ (3), and {[Co(ptc)0.5(phen)(H2O)2](H2O)2.5}∞ (4). Structural analysis reveals that complexes 1 and 2 both take one-dimensional polymeric chain structures with dinuclear and trinuclear units as nodes, respectively, which are further extended via the accessorial secondary interchain interactions, such as C–H···O H-bonding or aromatic π···π stacking interactions, to give rise to the relevant higher-dimensional frameworks. Compound 3 has a two-dimensional sheet structure that is further assembled to form a three-dimensional framework by interlayer π···π stacking interactions. Complex 4 is a one-dimensional ribbon-like array structure that is interlinked by the co-effects of intermolecular π···π stacking and C–H···π supramolecular interactions, resulting in a higher-dimensional framework from the different crystallographic directions. Moreover, complexes 1–4 exhibit strong solid-state luminescence emissions at room temperature, which mainly originate from intraligand π→π* transitions of ptc.

In the title centrosymmetric binuclear AgI complex, [Ag2(NO3)2(C12H10N4)2], each AgI center is coordinated by one pyridine and one benzotriazole N-donor atom of two inversion-related 2-(3-pyridylmeth­yl)-2H-benzotriazole (L) ligands, and an O atom of a coordinated NO3 − anion in a distorted T-shaped geometry. This forms a unique box-like cyclic dimer with an intra­molecular non-bonding Ag⋯Ag separation of 6.327 (2) Å. Weak inter­molecular Ag⋯O(nitrate) inter­actions [2.728 (4) and 2.646 (3) Å] link the binuclear units, forming a two-dimensional network parallel to (100). Inter­molecular C—H⋯O hydrogen-bonding inter­actions, involving the L ligands and the coordinated NO3 − anions, link the sheets, forming a three-dimensional framework.