Crystal Structure and Photophysical Properties of a Novel Dy-Hg Isonicotinic Acid Compound with One-Dimensional Chain-Like Cations.

A novel Dy-Hg compound [Dy(HIA)3(H2O)2]2n·2nHgCl4·nHgCl5·nH3O·3nH2O (1; HIA = isonicotinic acid) was prepared through a hydrothermal reaction and characterized by X-ray diffraction. The compound crystallizes in the space group of C2/c of the monoclinic system. The crystal structure of compound 1 has one-dimensional (1-D) chain-like cations. A photoluminescence experiment with a solid-state sample revealed that this compound exhibits a yellow emission band at 575 nm and, this emission band shall come from the 4f electron 4F9/2 ? 6H13/2 characteristic transfer of Dy3+ ions. The compound features CIE chromaticity coordinates of 0.5168 and 0.4824 in the yellow region. A UV-visible diffuse reflectance spectrum with a solid-state sample unveiled that this compound possesses a wide optical band gap of 3.39 eV.