Two novel 3-D bismuth oxalates with organic amines protruding in channels

Two novel 3-D oxalate-containing bismuth compounds of formula (C3N2H5)2 [Bi2(C2O4)4(H2O)2].2H2O 1 and [NH(C2H5)3][Bi3(C2O4)5] 2 were obtained by hydrothermal synthesis and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic P2/n space group with a=9.7541(13)A, b=17.7404(15)A, c=14.6321(6)A, β=97.280(3)o, Z=4, R1=0.0340 and wR2=0.0766 for unique 4734 reflections I>2σ(I). Compound 2 belongs to the orthorhombic Pbcn space group with a=14.803(4)A, b=19.783(7)A, c=8.202(2)A, Z=4, R1=0.0222 and wR2=0.0568 for unique 2472 reflections I>2σ(I). The BiIII centers have nine-fold coordination for 1 and eight-fold for 2 with the Bi atoms in distorted monocapped square antiprism and distorted dodecahedron, respectively. And oxalate ligands adopt different coordination modes: bidentate for 1, bidentate and tricoordinate for 2. Compounds 1 and 2 are both 3-D open-framework structures containing channels with guest molecules. These two compounds exhibit intense blue luminescence with the emission peaks at 419nm for 1 and 442nm for 2, respectively, in the solid state at room temperature. These compounds with novel structural frameworks could be useful in the field of photoactive materials