Akademik Veri Yönetim Sistemi
JOURNAL OF COORDINATION CHEMISTRY, cilt.71, sa.24, ss.4031-4046, 2018 (SCI-Expanded)
N,N '-Bis(pyridin-4-ylmethylene)naphthalene-1,5-diamine (L) acts as a bipyridine analogue linker ligand towards {Zn-7(mu(4)-O)(2)(OAc)(10)}, {Zn-2(NCS)(2)(OAc)(2)}, and {Zn(N-3)(2)} nodes and allows construction of three new 1-D coordination polymers, the linear chain [Zn-7(mu(4)-O)(2)(OAc)(10)(L)](n) (1), [Zn(NCS)(OAc)(L)](n) (2) in ladder-type geometry and the zigzag chain [Zn(N-3)(2)(L)](n) (3). Structural characterization reveals that in 1 acetate anionic ligands connect seven Zn(II) ions through the bridging coordination modes mu(3)-eta(1),eta(2) and mu(2)-eta(1),eta(1). The resulting heptanuclear node is located on an inversion center and therefore consists of four crystallographically distinct cations; their coordination spheres correspond to distorted octahedra or tetrahedra. The Zn(II) ions in polymer 2 exhibit distorted trigonal bipyramidal {ZnN3O2} coordination; mu(2)-eta(1),eta(1) coordinated acetate and terminal thiocyanate ligands lead to inversion-symmetric [Zn-2(NCS)(2)(OAc)(2)] secondary building units (SBU), which are further linked by the N,N '-bipyridine analogue L. Terminal coordination of two anionic azide ligands and the bridging bipyridine L result in coordination polymer 3, in which the cations adopt distorted tetrahedral {ZnN4} coordination. In all crystalline solids 1-3, adjacent 1-D chains interact through pi-pi stacking and non-classical (C - H center dot center dot center dot O, C - H center dot center dot center dot pi) hydrogen bonds, leading to 3-D supramolecular architectures. Differences in their 3-D arrangement are due to variations in the anionic co-ligands, subtle conformational differences in the semi-rigid linker and the variable coordination sphere about the zinc cations. Thermogravimetric investigations indicate differences in both thermal stability and decomposition mode. Natural bond orbital (NBO) analysis provides a convenient basis for investigating the intramolecular bonding interactions and delocalization effects in these molecular systems. Finally, solids 1-3 exhibit intense luminescence at room temperature.