Synthesis, crystal structure and thermal decomposition kinetics of the complex [Sm(BA)3bipy]2

The complex of [Sm(BA)(3)bipy](2) (BA = benzoic acid; bipy = 2,2'-bipyri dine) was obtained and characterized by elemental analysis, molar conductance, IR spectra, UV spectra, single crystal X-ray diffraction and TG-DTG techniques. The crystal is monoclinic with space group P2(l)/n. The unit cell parameters are: a = 14.157(2) angstrom, b = 15.416(3) angstrom, c = 26.079(4) angstrom, beta = 103.445(2)degrees. Two Sm3+ ions are connected by four carboxylic groups through bridging bidentate mode. Each center Sm3+ is eight-coordinated with a trigondodecahedron. The thermal decomposition behaviors of the title complex in a static air atmosphere were discussed by TG-DTG and IR techniques. The non-isothermal kinetics was investigated by using double equal-double step method and nonlinear integral isoconversional method. The mechanism function of the first decomposition step was determined. Meanwhile, the thermodynamic parameters (Delta H-#, Delta G(#) and Delta S-#) and kinetic parameters (activation energy E and pre-exponential factor A) were also calculated. The lifetime equation at mass-loss of 10% was deduced as In tau = -34.56 + 19299.15/T by isothermal thermogravimetric analysis. The title complex can be used in many areas such as extraction, separation, germicide, catalysis and functional materials and so on. (c) 2008 Elsevier B.V. All rights reserved.