Hydrothermal Synthesis and Structural Characterization of a Coordination Polymer Containing Heptanuclear Co₇(μ₃-OH)₈ Clusters

Abstract

The hydrothermally synthesized Co7(μ3-OH)8(μ-ox)3(μ-ppz)3 contains heptanuclear hydroxo-bridged Co(II) clusters in the form of corner-fused double cubanes. Each cluster is further bridged by six oxalate (ox) and six piperazine (ppz) ligands with 12 other clusters into a 3-D structure.

A novel three-dimensional metal-organic interpenetrating framework constructed from mixed adipate and 4,4 ′ -bipy ligands: [Co(OOC(CH 2 ) 4 COO)(4,4 ′ -bipy)] (adipate=HOOC(CH 2 ) 4 COOH, 4,4 ′ -bipy=4,4 ′ -bipyridine)

“…The O(1)-O(4) have bond valence sums of 1.70, 1.70, 1.86, and 1.85, respectively, [15]. These results indicate that all the oxygen atoms of adipate groups are deprotonated [16]. These results are consistent with the charge balance considerations of compound 1.…”

Synthesis and Structure of a New Organic–Inorganic Framework with Tetranuclear Clusters, [Co4(OH)2(H2O)2](C4H11N2)2[C6H2(COO)4]2·3H2O

“…With these ideas in mind, coordination polymers containing inorganic clusters, chains, and layers may be expected when parameters such as the choice of bridging ligands, the ligand-to-metal ratio, and the pH are optimized; and the hybrid organic}inorganic materials produced may have dual microporous and magnetic properties (5). We have been interested in synthesizing coordination polymers containing oxo-bridged polynuclear centers by hydrothermal (or solvothermal) syntheses in systems containing both bismonodentate N-donor and bis-bidentate O-donor bridging ligands (6). In such system the ful"llment of the coordination sphere of metal centers is more #exible because of the combined functional groups of the mixed ligands, and the pH of reactions can be "ne tuned by simply adjusting the mixed ligand ratios to the desired condition for producing interesting oxo-bridged transition metal clusters.…”

Durability of a PtSn Ethanol Oxidation Electrocatalyst

“…The magnetic susceptibilities of 1 were measured by using a crushed single crystalline sample under an applied field of 1 kOe for 1 at temperatures ranging from 2 to 300 K. The χ M vs. T and χ M T vs. T curves are provided in Figure 3. For complex 1 , spin‐orbital coupling of Co II ion gives rise to a χ M T product of 26.8 cm 3 · K · mol –1 at room temperature (Figure 3), which is higher than the spin‐only value of 13.1 cm 3 · K · mol –1 for seven non‐interaction high‐spin Co II ions assuming g = 2.0,34 and also higher than the value of 18.2 cm 3 · K · mol –1 for reported sample previously, [Co 7 (mmp) 6 (CH 3 O) 6 ] · (ClO 4 ) 2 , (Hmmp = 2‐methoxy‐6‐methylimino‐methyl‐phenol),17 but slightly smaller than the value of 29.8 cm 3 · K · mol –1 for the reported sample previously, [Co 7 (bm) 12 ] · (ClO 4 ) 2 · 13H 2 O [Hbm = (1H‐benzimidazol)‐methanol] 35. This can be explained by the orbital contribution to the magnetic moment of Co II .…”