The only feasible access to non‐face‐centered cubic (FCC) copper was by physical vapor deposition under high vacuum. Now, non‐FCC copper is observed in a series of alkynyl‐protected Cu53 nanoclusters (NCs) obtained from solution‐phase synthesis. Determined by single‐crystal X‐ray crystallography, the structures of Cu53(C≡CPhPh)9(dppp)6Cl3(NO3)9 and its two derivatives reveal an ABABC stacking sequence involving 41 Cu atoms. It can be regarded as a mixed FCC and HCP structure, which gives strong evidence that Cu can be arranged in non‐FCC lattice at ambient conditions when proper ligands are provided. Characterization methods including X‐ray absorption fine structure, XPS, ESI‐MS, UV/Vis, Auger spectroscopy, and DFT calculations were carried out. CuII was shown to successively coordinate with introduced ligands and changed to CuI after bonding with phosphine. The following addition of NaBH4 and the aging step further reduced it to the Cu53 NC.

No abstract

Seven new metal phosphonoacetates, namely, [Zn 7 (OH) 2 (ppat) 4 (H 2 O) 2 ] (1), H 3 O[Zn(ppat)] (2), [Zn 3 (4,4′-bpy) 6), and [Fe III (ppat)(H 2 O)] (7) (H 3 ppat ) phosphonoacetic acid, 4,4′-bpy ) 4,4′-bipyridine, dmpz ) N,N′-dimethylpiperazine) were hydrothermally synthesized by the in situ hydrolysis of triethyl phosphonoacetate route. X-ray crystallography reveals that 1 shows a two-dimensional layered structure containing octahedral, tetrahedral, and trigonal bipyramidal Zn sites and an unprecedented inorganic Zn-O ribbon; 2 has a threedimensional framework with one-dimensional dumbbell-shaped channels encapsulating protonated water molecules; 3 is a neutral three-dimensional framework constructed by [Zn(4,4′-bpy)] n 2n+ chains and [Zn(ppat)] n nlayers, two types of structural motifs; 4 shows a three-dimensional hydrogen bond network constructed by [Zn(ppat)]anionic layers and N,N′-dimethylpiperazinium cations; 5 is a layered structure containing inorganic Co-O chains consisting of edge-shared CoO 6 octahedra; 6 has a 3D hydrogen bond array constructed from [V 2 O 2 (ppat)] n 2nlayers and doubly protonated 4,4′-bpy cations; 7 crystallizes in a chiral space group and has a 3D four-connected framework with diamond topology. Magnetic measurements reveal antiferromagnetic behavior for 5, paramagnetic behavior for 6, and canted antiferromagnetic behavior for 7.

Metal–organic frameworks (MOFs) with excellent proton conducting ability are crucial to fuel cells, chemical sensors, and redox flow batteries, but achieving them remain a challenge because of the difficulty in simultaneous fulfillment of large number of proton carriers, high mobility of protons, and long-term durable proton conduction. To explore a simple, efficient, and general route toward highly proton-conducting MOFs, we propose herein an aliovalent substitution metal strategy for isostructural aminium-templated MOFs which benefit the acquisition of rich proton sources without modifying ligands or exchanging protic organic molecules. This idea is verified by 100-fold enhancement of conductivity in compounds (Me2NH2)2[Cd­(mdhbqdc)2] (Cd-BQ) and (Me2NH2) (Me2NH)­[In­(mdhbqdc)2] (In-BQ) (H2mdhbqdc = dimethyl 3,6-dihydroxy-2,5-benzoquinone-1,4-dicarboxylic acid) that feature three-dimensional diamond-like structures with two-dimensional intersected channels. Accompanied by the in situ formation of an anilicate ligand, a great number of −OH groups are grafted onto the inner wall of pores, which interact with neutral Me2NH and/or protonated Me2NH2 + cations via N–H···O hydrogen bonds. The high concentration of protons and dynamics of protic amines in the porous framework readily leads to a moderate conductivity of In-BQ (2.10 × 10–4 S cm–1, at 303 K under 95% RH) and an activation energy of 0.73 eV (95% RH). It should be noted that the aliovalent substitution of Cd­(II) for In­(III) results in the doubling of dimethylaminium proton carriers in Cd-BQ, indicating more frequent hopping and multiple proton-transfer pathways. This indication is supported by a very high protonic conductivity of 2.30 × 10–2 S cm–1 and a reduced activation energy of 0.48 eV under the same conditions. Molecular dynamics simulations visually elucidate the fact that compared with In-BQ, aliovalent-substituted Cd-BQ has shorter proton-migration distances, which in combination with more proton numbers results in more frequent hopping and sliding of protons, in agreement with the experimental results.

Seven cupric halide coordination polymers, namely [Cu5(OH)3Br3(ina)4] (1), [Cu5(OH)3Cl3(ina)4] (2), [Cu2(OH)Cl(ina)2] (3), [Cu3(OH)2Cl2(ina)2]·2H2O (4), [Cu3(OH)2Br2(ina)2]·2H2O (5), [Cu2Cl2(ina)2(H2O)2] (6), [Cu2Cl(ina)2(gca)(H2O)] (7), cupric complex templated cuprous halide [Cu(II)(Me-ina)2(H2O)][Cu(I)5Br7] (8), and organic templated cuprous halide Me2-ina[Cu2Br3] (9) (Hina = isonicotinic acid), were prepared from the starting materials of cupric halide and Hina via fine-tuning solvothermal reactions. According to valence states of copper, 1-7 are copper(II) complexes, 8 is a mixed-valent Cu(I,II) complex, while 9 is a Cu(I) compound. According to bonding types of halides, nine complexes can be classified as three types: complexes 1-3 include only normal X-Cu bond (X = halide); complexes 4-7 include normal X-Cu bond and X···Cu weak bond; complexes 8 and 9 include normal X-Cu bond and X···H-C halogen hydrogen bonds. Complexes 1 and 2 are isomorphic three-dimensional (3D) pcu topological metal organic frameworks (MOFs) with butterfly-like Cu4(μ3-OH)2X2 and steplike Cu6(μ3-OH)4 cores as nodes, showing strong ferromagnetic couplings. Complex 3 also is a pcu topological MOF with only butterfly-like Cu4(μ3-OH)2Cl2 clusters as nodes, presenting spin canting antiferromagnetic behavior. Isostructural 4 and 5 are Cu3(OH)2 clusters based two-dimensional (2D) (4,4) layers, which are extended into 3D eight-connected networks via weak Cu···X bonds, showing ferromagnetic coupling. Antiferromagnetic 6 is a simple one-dimensional coordination polymer, which is extended via weak Cu···Cl bonds into 3D (3,4)-connected networks. Paramagnetic 7 is a ladderlike polymer, which is extended into 2D (3,4)-connected layer via weak Cu···Cl bonds. The syntheses of polymeric cupric complexes 1-7 mainly result from differences in reactant ratio and pH value. Utilization of reducing methanol generated novel cubane-containing [Cu5Br7](2-) chain templated by paddlewheel-like [Cu(II)(Me-ina)2](2+) 8 and face-shared dimer-containing [Cu2Br3](-) chain templated by N-methylated and O-esterificated Me2-ina 9. Complex 9 exhibits a strong red emission and a weaker green emission upon excitation.