Metal–organic hybrid materials built with tetrachlorophthalate acid and different N-donor coligands: Structure diversity and photoluminescence

Abstract

Eight new metal–organic hybrid materials, namely {Cd(Tcph)(4,4′-bipy)1/2} (1), {[Cd2(Tcph)2(1,4-bimb)1/2(H2O)4]·H2O} (2), {Cd2(Tcph)2(1,4-bmimb)1/2(H2O)4} (3), {Cd(Tcph)(1,2-bmimb)} (4), {Cu(Tcph)(1,4-bimb)(H2O)} (5), {[Co(Tcph)(1,4-bimb)1/2(H2O)3]·(H2O)} (6), {Zn(Tcph)(1,2-bimb)} (7), {Cu2(Tcph)2(1,2-bimb)(H2O)4} (8), where Tcph=tetrachlorophthalate acid, 4,4′-bipy=4,4′-bipyridine, 1,4-bimb=1,4-bis(imidazol-1-ylmethyl)benzene, 1,4-bmimb=1,4-bis(2-methylimidazol-1-ylmethyl)benzene, 1,2-bimb=1,2-bis(imidazol-1-ylmethyl)-benzene, 1,2-bmimb=1,2-bis(2-methylimidazol-1-ylmethyl)benzene, have been synthesized and characterized. Their structures are determined by single crystal X-ray diffraction and further characterized by infrared spectra (IR) and thermogravimetric (TG) analyses. Complex 1, 4 and 7 display 2D layer structures. 1 possesses two-dimensional sheet containing an unusual [Cd(Tcph)] chains linked by 4,4′-bipy co-ligand, while 4 and 7 hold the similar 4-connected 44-sql nets. Complex 2 and 3 feature a similar three dimensional (3D) internal compensation structure with a topology of {42·63·8}2{63}. 5 is a novel 2-fold self-penetrating 3D network with 4-coordinated 65·8–CdSO4 subnets. The ladder-like chains of 6 are further connected through O–H···O interactions to yield a 3D supramolecular structure. 8 is a discrete tetranuclear complex. The thermal stabilities of 1–8 and the luminescent properties of 1–4 and 7 in the solid state are also discussed.