Syntheses, Crystal Structures And Properties Of Rigid Aromatic Carboxylate Cordination Compounds

The rational design and synthesis of coordination compounds are of great interest,owing to their elegant framework topologies as well as their tremendous potentialapplications in nonlinear optics, catalysis, luminescence, gas sorption, and magnetism.Studies in this field have been focused on the design and construction of newcoordination frameworks as well as the elucidation of their structure-functionrelationship. Twelve coordination compounds formulated as [Tb(ctd)(DMF)]n(1)，[Dy(ctd)(DMF)]n(2),[Mn2(pip)2(H2O)4]·4H2O(3),[Cd(pip)(H2O)2]·H2O(4),[Mn(pip)(H2O)2]·H2O(5),[Mn(pip)(4,4′-bipy)](6),[Co(pip)(4,4′-bipy)](7),[Co(pip)(pyz)](8),[Zn(Hpip)(HCO2)]·2H2O(9),[Mn3(pip)2(HCO2)2(H2O)2](10),[Co3(pip)2(HCO2)2(H2O)2](11) and [Zn(pip)(H2O)]·2H2O(12), were prepared bysolvothermal reactions based on [5′-carboxyl-[1,1′:3′,1′′-terphenyl]-4,4′′-dicarboxylicacid (H3ctd) and5-(Pyridin-4-yl)isophthalic Acid(H2pip). All compounds1-12werecharacterized by elemental analysis, IR spectra and X-ray single-crystal diffraction.Eight of them were measured by thermal gravimetric analysis and powder X-raydiffraction analysis. Structural analyses reveal that the compound1and2areisostructural, and each forms a three-dimensional (3D) structure possessingone-dimensional (1D) channels filled with coordinated DMF molecules. Compounds3,4and5possess two-dimensional (6,3) layered structures and further assembledinto a3D framework via π-π stacking and H-bonding interactions. In addition,4and5are also isostructural. Compounds6-9display two-fold interpenetrating3Dpillar-layer network. The adjacent layers are connected through4,4′-bipy, pyrazine(pyz) and formate as linkers. The resultant three-dimensional architecture of6-8canbe simplified as a (3,5)-connected hms network, and compound9exhibits a (3,4)-connected3D fsc framework with the Schl fli symbol of {63}{65.8}. Compounds6and7are almost identical in structure. Compounds10and11are isomorphous andpossess novel3D framework, they are trinuclear complexes. There are dinuclear zincrings in compound12, and it exhibits a (3,6)-connected2D bilayer kgd network with{43}2{46.66.83} topology. Moreover, the photoluminescence properties of1and2have been investigated; the resulting materials show strong solid-state emissions inthe visible region at room temperature.