Structural and luminescent properties of co-crystals of tetraiodoethylene with two azaphenanthrenes

Abstract

Two new co-crystals, tetraiodoethylene–phenanthridine (1/2), 0.5C2I4·C13H9N (1) and tetraiodoethylene–benzo[f]quinoline (1/2), 0.5C2I4·C13H9N (2), were obtained from tetraiodoethylene and azaphenanthrenes, and characterized by IR and fluorescence spectroscopy, elemental analysis and X-ray crystallography. In the crystal structures, C—I...π and C—I...N halogen bonds link the independent molecules into one-dimensional chains and two-dimensional networks with subloops. In addition, the planar azaphenanthrenes lend themselves to π–π stacking and C—H...π interactions, leading to a diversity of supramolecular three-dimensional structural motifs being formed by these interactions. Luminescence studies show that co-crystals 1 and 2 exhibit distinctly different luminescence properties in the solid state at room temperature.

Keywords

• co-crystallized molecules
• crystal structure
• tetraiodoethylene
• azaphenanthrenes
• luminescence