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The construction of secondary building units (SBUs) in versatile metal–organic frameworks (MOFs) represents a promising method for developing multi‐functional materials, especially for improving their sensitizing ability. Herein, we developed a dual small molecules auxiliary strategy to construct a high‐nuclear transition‐metal‐based UiO‐architecture Co16‐MOF‐BDC with visible‐light‐absorbing capacity. Remarkably, the N3− molecule in hexadecameric cobalt azide SBU offers novel modification sites to precise bonding of strong visible‐light‐absorbing chromophores via click reaction. The resulting Bodipy@Co16‐MOF‐BDC exhibits extremely high performance for oxidative coupling benzylamine (~100 % yield) via both energy and electron transfer processes, which is much superior to that of Co16‐MOF‐BDC (31.5 %) and Carboxyl @Co16‐MOF‐BDC (37.5 %). Systematic investigations reveal that the advantages of Bodipy@Co16‐MOF‐BDC in dual light‐absorbing channels, robust bonding between Bodipy/Co16 clusters and efficient electron‐hole separation can greatly boost photosynthesis. This work provides an ideal molecular platform for synergy between photosensitizing MOFs and chromophores by constructing high‐nuclear transition‐metal‐based SBUs with surface‐modifiable small molecules. [ABSTRACT FROM AUTHOR]

Constructing multiple functional geometric frustration magnets is a hot topic in solid state chemistry and material science. Herein, a two‐dimensional (2D) parallel interpenetrating "star" net complex [HDMPDA][Fe6(μ3‐O)2(μ‐O2CH)15] (1) was obtained successfully with HDMPDA (DMPDA=N, N'‐dimethyl‐1,3‐propanediamine) as charge balancer. The dipole reorientation of the rotator [HDMPDA]+ in the complex brings a structure transition which leads dielectric relaxation close to room temperature. Despite strong antiferromagnetic coupling existing between ions in the net, long‐range order temperature TN of the complex is suppressed to 4.2 K by geometric frustration. Interestingly, below TN, a canted antiferromagnetic state, accompanied with slow magnetic relaxation, is detected due to the lack of enough magnetic coupling between 2D layers. Thus, 1 is a particular multifunctional magnetic frustration material containing two different types of relaxations. [ABSTRACT FROM AUTHOR]

Four carboxylate-bridged GdIII complexes ( 1- 4) with 1D/2D structures have been synthesized by using the hydrothermal reaction of Gd2O3 with various carboxylate ligands. Compounds 1 and 2 contained the same [2n] GdIIIOH ladders, but with different crystallographically independent GdIII ions, whilst the structures of compounds 3 and 4 were composed of [Gd4(μ3-OH)2(piv)8(H2O)2]2+ units and 1D ladder GdIII chains, respectively. Antiferromagnetic interactions occurred in compounds 1- 3, owing to their small GdOGd angles, whereas ferromagnetic coupling occurred in compound 4, in which the GdOGd angles were larger. These complexes exhibited a distinct magnetocaloric effect (MCE), which was affected by their different magnetic densities and exchange interactions. Among these compounds, complex 4 presented the largest MCE (−Δ Smmax=43.6 J kg−1 K−1), the lowest Mw/ NGd ratio (the highest magnetic density), and weak ferromagnetic coupling. Therefore, a lower Mw/ NGd ratio and weaker exchange interactions (a smaller absolute value of θ) between GdIII ions resulted in a larger MCE for the GdIII complexes. [ABSTRACT FROM AUTHOR]

The assembly of CuII, MII (CoII or NiII), azido, and isonicotinate acid N-oxide under hydrothermal conditions straightforwardly gives two isomorphic heterometallic 3d-3d azido complexes formulated [Cu2M(N3)4(INO)2(H2O)4]∞ (INO = isonicotinate N-oxide; M = Co for 1 and Ni for 2). In the structure of the complexes, CuII ions have a trigonal-bipyramidal-coordinated configuration, whereas the MII ions have octahedral geometry with two water molecules in the apical positions. The structure of the complexes is based on azido-carboxylate mixed-coordination Cu-M-Cu trimers, which are further linked by double end-on (EO) azido anions through the CuII ions to form a chain structure, and the 1D structure can be described as EO azido/ syn-syn carboxylates and double EO azido mixed-bridge spin-sequence chains with -1/2- J1-3/2- J1-1/2- J2-1/2- for 1 and -1/2 -J1-1 -J1-1/2 -J2 -1/2- for 2. Magnetic studies indicated that 1 and 2 are both metamagnets for the weak antiferromagnetic interactions between the ferromagnetic chains. [ABSTRACT FROM AUTHOR]

Review: 152 refs. [ABSTRACT FROM AUTHOR]

In the crystal structure of the binuclear title complex, [Co(N(3))(2)(C(12)H(8)N(2))](n), each Co(II) cation is coordinated by two N atoms from one chelating 1,10-phenanthroline ligand and four azide ligands in a slightly distorted octa-hedral coordination. The two Co(II) cations of the binuclear complex are related by an inversion centre and are bridged by two symmetry-related azide ligands in both μ(1,1) and μ(1,3) modes. The μ(1,3) bridging mode gives rise to an infinite one-dimensional chain along the a axis, whereas the μ(1,1) bridging mode is responsible for the formation of the binuclear Co(II) complex.

In the title complex, [Fe(C(2)O(4))(C(5)H(4)N(2)O(4))](n), the Fe(II) ion is coordinated by two oxalate anions and a pyrimidine-2-carb-oxy-lic acid ligand in a slightly distorted octa-hedral geometry. Each oxalate anion chelates to two Fe(II) ions, forming chains along the a axis. The chains are further connected by O-H⋯O and C-H⋯O hydrogen bonds, stabilizing the structure. An intra-molecular O-H⋯N inter-action results in a five-membered ring.

In the crystal structure of the title compound, [Ag(C(7)H(3)N(2)O(2)S)](n), the Ag(I) atom is coordinated by two N atoms and three O atoms of four organic ligands forming a distorted square pyramid. The carboxyl-ate group acts as a bidentate ligand on one Ag(I) atom and as a bridging group for a symmetry-related Ag(I) atom, forming a dimer. Futhermore, the two N atoms of two thia-diazole rings bridge a third symmetry-related Ag(I) atom, forming a six-membered ring. These two frameworks, AgO(2)Ag and AgN(4)Ag, extend in three directions, forming a three-dimensionnal polymer. The whole polymer is organized around inversion centers.

In the title compound, [Cu(3)(C(5)H(3)N(2)O(2))(2)(N(3))(4)](n), one of the Cu(II) atoms lies on an inversion centre and is octa-hedrally coordinated by two bidentate chelating pyrimidine-2-carboxyl-ate ligands and two azide anions, each of which gives an N:N-bridge to the second inversion-related Cu(II) centre in the formula unit. The second Cu(II) atom is five-coordinated with a distorted square-pyramidal coordination sphere comprising a single bidentate chelating pyrimidine-2-carboxyl-ate anion and three azide N anions, two of which doubly bridge centrosymmetric Cu(II) centres, giving a two-dimensional network structure extending parallel to (010).

The asymmetric unit of the title compound, [Co(C(6)H(12)NO(4))(2)], contains one half-mol-ecule with the Co(II) ion situated on an inversion center. Inter-molecular O-H⋯O hydrogen bonds generate a three-dimensional hydrogen-bonding network, which consolidates the crystal packing.

In the title compound, [Co(C(5)H(3)N(4)O)(N(3))(H(2)O)](n), the cobalt ion is coordinated by three N atoms of two organic ligands, two N atoms of two azide anions and one water mol-ecule in a distorted octa-hedral geometry. The metal atoms are connected via the ligands into layers, which are further connected by O-H⋯N and O-H⋯O hydrogen bonding.