Assembly of Three New Co2/Mn5/Co5-Cluster-Based Metal–Organic Frameworks: Syntheses, Structure, Thermal Stability and Magnetic Properties

Novel Co5 Cluster Based Triazole Bridged Cobalt‐Fluorophosphate: Synthesis, Structure, Magnetic and Heterogeneous Catalytic Epoxidation Studies

“…The bond distances and angles are in good agreement with the literature values. [22][23] In the structure, one Co2 center is surrounded by four Co1 centers forming a pentanuclear cluster based complex (Figure 3), the distance amongst Co1 center and Co2 centers is 3.136 Å, similar to those Co 5 clusters within MOF in literatures. [22][23] The five Co(II) centers remain in the same plane (Figures 3).…”

“…[22][23] In the structure, one Co2 center is surrounded by four Co1 centers forming a pentanuclear cluster based complex (Figure 3), the distance amongst Co1 center and Co2 centers is 3.136 Å, similar to those Co 5 clusters within MOF in literatures. [22][23] The five Co(II) centers remain in the same plane (Figures 3). Examples of this type of Co 5 cluster are found in MOF system (CCDC database identifier code: GENHUG [22] and CUBXUV [23] ), where the Co 5 clusters are linked by organic ligands.…”

“…[22][23] The five Co(II) centers remain in the same plane (Figures 3). Examples of this type of Co 5 cluster are found in MOF system (CCDC database identifier code: GENHUG [22] and CUBXUV [23] ), where the Co 5 clusters are linked by organic ligands. Co 5 cluster also can be in very different shape (CCDC database identifier code: OWAXOC, [24] Figure S1).…”

“…The magnetic studies of compound 1 were carried out between 5 and 300 K. Plot of χ M T versus T (Figure 6), where χ M is the molar magnetic susceptibility, revealed that the χ M T value at 300 K (12.6 cm 3 mol À 1 K) is higher than the expected one for five non-interacting Co(II) ions with S = 3/2 and g = 2.0 (χ M = 9.35 cm 3 mol À 1 K), which is an clear indication of the orbital contribution (i. e., g > 2.0) to the magnetic moment, being characteristic of a Co(II) ion in an octahedron geometry with 4 T 1g ground state. [22] Upon cooling, χ M T remains approximately constant until ~200 K. At 5.3 K, χ M T decreases to 1.82 cm 3 mol À 1 K, which can be ascribed to either antiferromagnetic interactions and/or zero-field splitting (ZFS). However, these variations in the χ M T are relatively weak, so that the reciprocal susceptibility versus temperature fits very well to the Curie-Weiss law (Figure 6), leading to a Curie constant, C =…”