ZnL2Cl4 schiff base complexes were synthesized by using l-amino-4-methyl piperazine salicylic acid and zinc chloride in absolute ethanol, and characterized by element analysis and fluorescence of solid. Crystal structure of complexes was further determined by X-ray diffraction and showed that Zn2+ was coordinated by four chlorine atoms and aggregated into a three-dimensional framework via intermolecular hydrogen bonds. The complex was in a monoclinic system of space group C2/c with a = 12. 0757(12) nm, 6 = 8. 9859(8) nm, c = 27. 435(3) nm, β=98. 9450(10)°, Z=4,F(000) = l 344,Dc=l. 463 g · cm-3,μ = 1.231 mm-1. Both the L and ZnL2Cl4 were thermally stable and emitted intensive blue fluorescence. Determined by a microcalorimeter at 298. 15 K, the dissolution enthalpy of Zinc chloride and L in ethanol, as well as the liquid phase reaction formation enthalpy of complex were (7. 150 ± 0. 022), ( — 32. 587 + 0. 307) and (3. 745 ± 0. 035)kJ · mol-1 , respectively. The change of solid phase standard molar reaction enthalpy was obtained through a thermochemical cycle as ( — 54. 279 + 0. 671) kJ · mol-1.%在无水乙醇中,用1-氨基-4-甲基哌嗪缩水杨醛(L)与ZnCl2合成了希夫碱配合物ZnL2Cl4,对其进行了元素分析及固体荧光表征,并用X-射线衍射测定了其单晶结构.结果表明,Zn2+与4个Cl形成配位键,并与配体以分子间氢键形式联接成三维超分子结构.晶体属于单斜晶系,空间群为C2/c,晶胞参数a=12.0757(12) nm,b=8.9859(8) nm,c=27.435(3) nm,β=98.9450(10)°,V=2 940.8(5) nm3,Z=4,F(000)=1 344,Dc=1.463 g/cm3,μ=1.231 mm-1.该L及ZnL2Cl4均有较好的发光性质,发出蓝色荧光.298.15K下,ZnCl2和L在无水乙醇中的溶解焓及配合物液相反应生成焓分别为(7.150±0.022),(-32.587±0.307),(3.745±0.035) kJ/mol,热化学循环求得固相标准摩尔反应焓变为(-54.279±0.671) kJ/mol.
展开▼
