Syntheses, crystal structures and luminescent properties of three novel manganese coordination polymers with two-dimensional (6,3) honeycomb and (4,4) networks

Three novel two-dimensional coordination polymers {[Mn(ttmb)(NCS)2(H2O)]·1.5H2O}n (1), {[Mn(ttmb)2(H2O)2](PF6)2·5H2O}n (2) and {[Mn(ttmb)(1,4-bdc)(H2O)2]·1.5H2O}n (3) were synthesized by the reaction of 1,3,5-tri(1,2,4-triazol-1-ylmethyl)-2,4,6-trimethylbenzene (ttmb), Mn(II) salts, or 1,4-benzenedicarboxylate (1,4-bdc). In 1, each ttmb ligand shows a tri-monodentate coordination mode, and bonds three Mn(II) atoms to form an undulated (3,3)-connected two-dimensional (6,3) honeycomb network. In 2, each ttmb ligand shows a two-monodentate coordination mode, and connects two Mn(II) atoms to extend a two-dimensional (4,4) network in 2. In 3, ttmb and 1,4-bdc ligands both show the bis-monodentate coordination mode, and connect two Mn(II) atoms to extend an undulated two-dimensional (4,4) network in 3. 1, 2 and 3 display the luminescence maxima at 426, 409 and 419 nm, respectively, in the solid state at room temperature.

► Flexible tri(triazole) ligand Mn(II) MOFs with NCS−, PF6- and 1,4-benzenedicarboxylate.
► (3,3)-Connected two-dimensional (6,3) honeycomb network.
► Two-dimensional (4,4) network.
► Luminescent emission.