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Two novel isomorphous 2D NiII/CoII-NiII Metal-Organic Frameworks (MOFs) with tetrazole-1-acetate ligands have been synthesized and structurally characterized. And then they were calcined in air to obtain Ni/Co3O4-doped NiO electrodes. Compared to the homometallic MOF-derived oxide, the heterometallic MOF-derived bimetal oxides presented higher coulombic efficiency, better cycle performance, larger specific capacity as lithium-ion batteries anodes.

International audience; Solid solution of Hydrogen bonded networks of formula ((1-2H +)3x(2-2H +)3(1-x)([Fe(CN)6] 3-2)). nH2O, where (1-2H +) and (1-2H +) are bisamidinium H bond donor entities, have been synthetized and structurally analysed. The H bonded systems display a honeycomb-like structure, and depending on the x value, three different pavages of the (6,3) system are observed, leading to three different phases. The precise location of the H bond donor cations (2-2H +) have been performed, evidencing H bonding between adjacent cations. Thermal properties of the solid solutions have been performed.

Two new coordination complexes with tetrazole heterocycle ligands bearing acetate groups, [Co(L)2]n (1) and [Co3(L)4(N3)2·2MeOH]n (2) (L=tetrazole-1-acetate) have been synthesized and structurally characterized. Single crystal structure analysis shows that the cobalt-complex 1 has the 3D 3,6-connected (42.6)2(44.62.88.10)-ant topology. By introducing azide in this system, complex 2 forms the 2D network containing the [Co3] units. And the magnetic properties of 1 and 2 have been studied.

A novel open thermosyphon-type thermal storage unit is presented to improve design and performance of heat pipe type thermal storage unit. In the present study, tubular canisters filled with a solid–liquid phase change material are vertically placed in the middle of the thermal storage unit. The phase change material melts at 100 °C. Water is presented as the phase-change heat transfer medium of the thermal storage unit. The tubular canister is wrapped tightly with a layer of stainless steel mesh to increase the surface wettability. The heat transfer mechanism of charging/discharging is similar to that of the thermosyphon. Heat transfer between the heat resource or cold resource and the phase change material in this device occurs in the form of a cyclic phase change of the heat-transfer medium, which occurs on the surface of the copper tubes and has an extremely high heat-transfer coefficient. A series of experiments and theoretical analyses are carried out to investigate the properties of the thermal storage unit, including power distribution, start-up performance, and temperature difference between the phase change material and the surrounding vapor. The results show that the whole system has excellent heat-storage/heat-release performance.

Different ways of anions introduction were applied to construct cluster-based frameworks, owning to the versatile coordination ability of the formate anion and its sensitivity to the pH value of the reaction system. Three tetra-, penta-, and hexanuclear cluster-based cobalt-organic frameworks, [Co2(L)3(HCO2)·MeOH]n (1), [Co5(L)6(OH)2(NO3)2·2H2O]n (2), and [CoL(HCO2)]n (3) [L = (E)-3-(pyridin-3-yl)acrylate], have been successfully synthesized. In these complexes, each CoII cluster is linked by twelve L ligands with different connectivities to generate unique topological nets. In 1, two formate anions link four CoII ions forming a tetranuclear cluster, and each of the tetranuclear clusters is connected to eight neighbors by L ligands, giving an 8-connected 36418536 net. In 2, the pentanuclear cluster is formed by five CoII ions linked through two OH– and six carboxylate groups, which are further connected by L ligands to afford a pcu (primitive cubic lattice) net. Different from 1 and 2, complex 3 is a 2-fo...

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.

Three new CoII–azido complexes, [Co3(L)2(o-BDC)2(N3)2]n (1), [Co3(L)2(m-BDC)2(N3)2]n·nH2O (2), and [Co2(L)2(p-BDC)(N3)2]n·2nMeOH (3) [o-BDC = 1,2-benzenedicarboxylate, m-BDC = 1,3-benzenedicarboxylate, p-BDC = 1,4-benzenedicarboxylate, and L = di(1H-imidazol-1-yl)methane], have been constructed from di(1H-imidazol-1-yl)methane, azido, and different aromatic dicarboxylates under hydrothermal conditions. Complex 1 takes a dia topology with the Co3 units as connecting nodes, and complex 2 is a two-dimensional sql layer that further extends to a three-dimensional (3D) supramolecular network via π···π interaction between m-BDC ligands, while complex 3 forms a 3D pcu network based on Co2 units as nodes. The investigaton of magnetic properties of complexes 1–3 demonstrates that they all display ferromagnetic coupling between CoII ions but antiferromagnetic interaction between Co3 or Co2 units.

The reactions of Mn(II) ions with azido ligands in the presence of nicotinic/isonicotinic acids gave two manganese(II) azido coordination polymers, [Mn(3)(L(1))(2)(N(3))(4)](n).nH(2)O (1) and [Mn(2)(L(2))(N(3))(3)](n) (2), where L(1) = nicotinate and L(2) = isonicotinate, with different topological structures. Complex 1 consists of 2D azido-Mn(II) planes, which is further linked by L(1) to form a 3D framework with unprecedented 3,6-connected 4-nodal net topology, and complex 2 presents an unprecedented 3,4,6-connected 6-nodal 3D azido-Mn(II) structure with L(2) as the coligand. Magnetic susceptibility measurements reveal dominant antiferromagnetic coupling existing in 1 and 2. Complex 1 is a spin-competitive system and enters into a weak ferromagnetic-to-magnetic phase transition at the critical temperature of 6 K due to spin canting. Complex 2 is an antiferromagnet and exhibits field-induced spin-flop behavior.

Using two structurally related benzoates bearing different H-bond acceptors as co-ligands, three new azido-CuII compounds, [Cu(L1)(N3)(H2O)]n (1), [Cu(L1)(N3)(MeOH)]n (2), and [CuL2HL2(N3)3(H2O)]n (3) (HL1 = 4-nitrobenzoic acid; HL2 = 2-phenyl-4-quinolinecarboxylic acid), have been synthesized and structurally characterized. 1 is a carboxylate/EO-azido bridged copper chain, forming 3D structure by H-bonds, and 2 has a similar chain structure as 1 but forming a 2D structure by H-bonds, while 3 is a 3D supramolecular network with ternary center H-bonds. Magnetic study indicates that domain ferromagnetic coupling interactions were found to exist in complexes 1 and 3.

The X-ray crystal structures, magnetic susceptibilities from 2 to 300 K, and theoretical analyses of the magnetism for 1D and trinuclear azido Cu(II) carboxylate complexes [Cu(1.5)(hnta)(N(3))(2)(H(2)O)](n) (1) and [Cu(3)(hnta)(4)(N(3))(2)(H(2)O)(3)] (2), respectively, where hnta is 6-hydroxynicotinate, are described. Although both exhibit strong ferromagnetic coupling, discrete complex 2 exhibits long-range ferromagnetic ordering, while the very similar 1D system 1 does not. Density functional calculations provided accurate J values and allowed rationalization of the ferromagnetic coupling in terms of the magnetic orbitals and spin densities.

A new 3-D mixed valence copper-azido coordination polymer, [Cu I · Cu II (N 3 )(pzc) 2 (H 2 O)] n 1 , has been synthesized and characterized, and its magnetic properties studied. In this compound, the azide acts as rare asymmetric μ 1,1,3 bridging mode. The azide ligands and the Cu(2) ions act as 3-connecting nodes, and the Cu(1) ions act as 4-connecting nodes. The overall net takes rare topology with the Schlafli symbol of (6.8 2 )(6.8 2 )(6.8 5 ).

Two new 3D copper(II) azido isomers, [Cu(N3)(nic)]infinity (1 and 2) (nic = nicotinate), have been synthesized and characterized. To the best of our knowledge, 1 is the first metal azido complex showing rutile-type topology, while 2 is a chiral compound obtained by spontaneous resolution upon crystallization.

The hydrothermal reaction of Ni(NO(3))(2).6H(2)O, NaN(3) phenanthroline and nicotinic acid yielded a one-dimensional (1D) complex, [Ni(1.5)(N(3))(2)(phen)(nic)](n) (1) (phen = phenanthroline, nic = nicotinate), which is a new example of the named orbital countercomplementarity-like complex. In 1, the nicotinate shows mu(3)-nic-N,O,O coordination mode, and the azide groups adopt mu(1,1) bridging mode linking Ni(II) ions to form a rare trinuclear Ni(II) unit bridged by a double mu(1,1) azido.

A new three-dimensional Mn(II) complex, [Mn(3)(HCO(2))(2)(L)(2)(OCH(3))(2)], 1 (L = nicotinate N-oxide), was synthesized by solvothermal reaction and magnetically characterized. Complex 1 exhibits an unprecedented 3,6-connected 5-nodal net topology with Schlafli notation {4(2);6}4{4(3)}2{4(6);6(6);8(3);10}2{4(8);6(6);8} and was assigned as a homospin ferrimagnet. Interestingly, when 1 was placed in air for ca. one month, the methoxy anions in 1 were gradually exchanged by hydroxyl anions and 1 underwent a single-crystal-to-single-crystal structural transition to a new but similar complex, [Mn(3)(HCO(2))(2)(L)(2)(OH)(2)] x 4 H(2)O, 2. The anion exchange and water molecules filling the channels of 2 affect the magnetic behavior at low temperature compared to that of 1.

Through the use of a series of structurally related benzoates bearing different substituents as coligands, three new azido-copper compounds, [Cu(benzoate)(N(3))](n) (1), [Cu(2-methyl-benzoate)(N(3))](n) (2), and [Cu(1-naphthoate)(N(3))](n) (3), have been successfully obtained and structurally and magnetically characterized. Single-crystal structure analyses indicated that the uncoordinating substituents in the benzoates greatly affect the structure of the complexes. Complex 1 displays isolated ferromagnetic chains with the largest Cu-N-Cu angle in known carboxylate/end-on-azido mixed-bridged copper systems, while complexes 2 and 3 were 2D coordination polymers, containing mu-(1,1,3,3) and mu-(1,1,3) bridging azides and exhibiting new azido-copper networks with (4(4)) and (4.8(2)) topologies, respectively. Furthermore, 2 was a chiral complex obtained through spontaneous resolution. In the low-temperature range, both 2 and 3 showed spontaneous magnetization with characteristics of soft ferromagnetic magnetism with phase transition temperatures of 13 and 10 K, respectively.

A novel one-dimensional manganese(II) azido complex, [Mn2(N3)4(phen)2]n (1), in which the azido bridging ligands take on an unusual new type of combination with the metal center as the sign of [−EO−EO−EO−EE−]n, has been hydrothermally synthesized, and its magnetic properties have been studied.

A new 3D porous Ni(II)-azido complex has been synthesized and characterized and exhibits guest sorption properties explored by single-crystal to single-crystal transformations and linear ferromagnetic chains held together by a Ni-isonicotinate framework.