On the Border between Low-Nuclearity and One-Dimensional Solids: A Unique Interplay of 1,2,4-Triazolyl-Based {CuII5(OH)2} Clusters and MoVI-Oxide Matrix

• DOI: 10.1021/acs.inorgchem.8b00616
• Publication Date: 2018-05-09T13:40:47Z
• Authors: Andrey B. Lysenko; Oksana A. Bondar; Ganna A. Senchyk; Eduard B. Rusanov; Monika Srebro-Hooper; James Hooper; Krunoslav Prsa; Karl W. Krämer; Silvio Decurtins; Oliver Waldmann; Shi-Xia Liu
• Keywords: Bridging ligand; Hydrothermal Synthesis; 1,2,4-Triazole

A pentanuclear CuII5-hydroxo cluster possessing an unusual linear-shaped configuration was formed and crystallized under hydrothermal conditions as a result of the unique cooperation bridging 1,2,4-triazole ligand ( trans-1,4-cyclohexanediyl-4,4'-bi(1,2,4-triazole) tr2 cy)), MoVI-oxide, CuSO4. This structural motif can be rationalized by assuming in situ generation {Cu2Mo6O22}4- anions, which represent heteroleptic derivatives γ-type [Mo8O26]4- further interlinked [Cu3(OH)2]4+ cations through [ N- N] bridges. The framework structure resulting compound [Cu5(OH)2( cy)2Mo6O22]·6H2O (1) is thus built up from neutral heterometallic {Cu5(OH)2Mo6O22} n layers pillared with tetradentate cy. Quantum-chemical calculations demonstrate that exclusive site parent γ-[Mo8O26]4- into CuII inserts corresponds has lowest defect ("MoO2 vacancy") formation energy, demonstrating how local metal-polyoxomolybdate chemistry express itself final crystal structure. Magnetic susceptibility measurements 1 show strong antiferromagnetic coupling within Cu5 chain exchange parameters J1 = -500(40) K (-348(28) cm-1), J2 -350(10) (-243(7) cm-1) g 2.32(2), χ2 6.5 × 10-4. Periodic quantum-chemical reproduce character connect it effective ligand-mediated spin mechanism comes about favorable arrangement between Cu centers OH-, O2-, cy ligands.