Synthesis and structural determination of three metal-organic frameworks in a Co-3-amino-1,2,4-triazole system

摘要

The hydrothermal reactions of cobalt(II) salts with 3-amine-1H-1,2,4-triazole (Hatrz) result in two kinds of coordination polymers, namely, 2D isoreticular layers based on a binuclear unit Co(atrz)Br (1) and Co(atrz)I (2), and 3D alternating layer architecture of Co_5(atrz)_7(N_3)_3 (3), which were structurally charac_terized by single-crystal X-ray diffraction techniques. Thermostabilities of all compounds were examined by thermogravimetric analysis. Isostructural compounds 1 and 2 display a two-dimensional layer struc_ture where Co centers are linked by μ(1,2,4)-atra-anions to form isoreticular layers containing sixteen-mem_bered rings. Compound 3 is a 3D alternating layer architecture, which are based on parallel 1D chains and bimetal unit [N_3Co-(___(1,4)-atrz)-CoN_3]. The thermogravimetric analysis results of compounds 3 show that tremendous heat is released from its thermal decomposition, which indicates that the compound qualifies as a high-energy candidate.