Structure and Luminescence of Carboxylic Acid Samarium and Europium Complexes

摘要

Two crystals,[Sm(Hcpna)(cpna)·3H2O]n (1) and [Eu(Hcpna)(cpna)·2H2O]n (2),have been synthesized by solvothermal method based on Sm3+ and Eu3+ with multiple acid ligands 5-(4-carboxyphenoxy)nicotinic acid (H2cpna),and the new complexes have been characterized by single-crystal X-ray diffraction,elemental analysis,IR spectroscopy,thermogravimetric analysis and fluorescence analysis.Complex 1 exhibits a 1D chain structure.It crystallizes in the triclinic system,space group P-1 with a =5.9738(11),b =12.528(2),c =18.021(4) (A),a =93.156(3)°,β =98.067(3)°,γ =92.692(3)°,V =1331.3(4) (A)3,Z =2,S =1.069,F(000) =702,R =0.0277 and wR =0.0688 (Ⅰ ＞ 2σ(Ⅰ)).Complex 2 shows a two-dimensional network structure,which crystallizes in monoclinic system,space group C2/c with a =13.6733(19),b =18.422(3),c =10.4307(15) (A),β =93.881(2)°,V=2621.4(7) (A)3,Z =4,S =1.110,F(000) =1372,R =0.0302 and wR =0.0811 (Ⅰ＞2σ(Ⅰ)).The solid-state fluorescent test results show tcomplex 1 has weaker fluorescence intensity than the ligand.However,complex 2 has excellent fluorescence properties,and can emit bright red light under the irradiation of ultraviolet lamp.