Three complexes, [Pr(NO3)3(HL)2] (1), [Nd(NO3)3(HL)2] (2) and [Er(NO3)3(HL)2] ·0.5H2O (3), were synthesized from the reaction of a Schiff base ligand 2-[ (4-methylphenylimino)methyl ]-6-methox...Three complexes, [Pr(NO3)3(HL)2] (1), [Nd(NO3)3(HL)2] (2) and [Er(NO3)3(HL)2] ·0.5H2O (3), were synthesized from the reaction of a Schiff base ligand 2-[ (4-methylphenylimino)methyl ]-6-methoxyphenol (C15 H15 NO2, HL) with Ln(NO3)3·6H2O (Ln = Pr, Nd, Er). Characterization by single-crystal X-ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis, ^1H NMR and thermal analysis shows the title complexes are neutral molecules where the central Ln( Ⅲ) ion is ten-coordinated in biapical anti-hexahedron prism geometry, with four oxygen atoms of the phenolic hydroxy and methoxy groups in the two bidentate Schiff base ligands and six oxygen atoms provided by the three bidentate NO3 - anions. Additionally, the kinetic mechanism of thermal decomposition of complex 3 was determined with a TG-DTG curves by both integral and differential methods. The functions of thermal decomposition reaction mechanism and the equation of kinetic compensation effect were obtained.展开更多
The title complex, Zn(C24H13NO)2Cl21, has been synthesized by the reaction of zinc chloride with Schiff base ligand N-salicylidene-p-toluidine and its structure was determined by single-crystal X-ray diffraction. Th...The title complex, Zn(C24H13NO)2Cl21, has been synthesized by the reaction of zinc chloride with Schiff base ligand N-salicylidene-p-toluidine and its structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group Cc with a = 14.896(3), b = 12.506(2), c = 15.352(3) A,β = 114.711 (4)°, V = 2598.0(8) A^3, C28H26ZnCl2N2O2, Mr = 558.80, Z = 4, Dc = 1 .429 g/cm^3,μ = 1.179 mm^-1, Flack parameter = 0.027(19), F(000) = 1152, R = 0.0709 and wR = 0.1041 for 3117 observed reflections (Ⅰ 〉 2σ(Ⅰ)). In complex 1, the center Zn ion is four-coordinated by two O atoms from two Schiff base ligands and two Cl atoms in a distorted tetrahedral geometry. Additionally, the thermal decomposition of complex 1 as well as its kinetic mechanisms and equations is studied under the non-isothermal integral and differential methods in air by TG-DTG curves.展开更多
The thermal decomposition of 2-(4-methoxycarbonylphenyl)-5-nitryl-6-hydroxybenzoxazole(MNB) in N2 atmosphere was studied by thermogravimetry(TG) and differential thermogravimetry(DTG).It is a sequential process.The mo...The thermal decomposition of 2-(4-methoxycarbonylphenyl)-5-nitryl-6-hydroxybenzoxazole(MNB) in N2 atmosphere was studied by thermogravimetry(TG) and differential thermogravimetry(DTG).It is a sequential process.The molecular bond orders were calculated by GAMESS method and the IR spectra of MNB and its intermediates in thermal decomposition at various temperatures were determined.The mechanism of the thermal decomposition has been discussed,the C-N bond breakdown and the nitro group elimination occurred in the initial step of the decomposition.The thermal decomposition kinetic parameters such as apparent activation energy E=115.5kJ·mol-1,pre-exponential factor A = 1.698×1010 min-1 and apparent reaction order n = 0 were obtained according to test data.展开更多
文摘Three complexes, [Pr(NO3)3(HL)2] (1), [Nd(NO3)3(HL)2] (2) and [Er(NO3)3(HL)2] ·0.5H2O (3), were synthesized from the reaction of a Schiff base ligand 2-[ (4-methylphenylimino)methyl ]-6-methoxyphenol (C15 H15 NO2, HL) with Ln(NO3)3·6H2O (Ln = Pr, Nd, Er). Characterization by single-crystal X-ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis, ^1H NMR and thermal analysis shows the title complexes are neutral molecules where the central Ln( Ⅲ) ion is ten-coordinated in biapical anti-hexahedron prism geometry, with four oxygen atoms of the phenolic hydroxy and methoxy groups in the two bidentate Schiff base ligands and six oxygen atoms provided by the three bidentate NO3 - anions. Additionally, the kinetic mechanism of thermal decomposition of complex 3 was determined with a TG-DTG curves by both integral and differential methods. The functions of thermal decomposition reaction mechanism and the equation of kinetic compensation effect were obtained.
文摘The title complex, Zn(C24H13NO)2Cl21, has been synthesized by the reaction of zinc chloride with Schiff base ligand N-salicylidene-p-toluidine and its structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group Cc with a = 14.896(3), b = 12.506(2), c = 15.352(3) A,β = 114.711 (4)°, V = 2598.0(8) A^3, C28H26ZnCl2N2O2, Mr = 558.80, Z = 4, Dc = 1 .429 g/cm^3,μ = 1.179 mm^-1, Flack parameter = 0.027(19), F(000) = 1152, R = 0.0709 and wR = 0.1041 for 3117 observed reflections (Ⅰ 〉 2σ(Ⅰ)). In complex 1, the center Zn ion is four-coordinated by two O atoms from two Schiff base ligands and two Cl atoms in a distorted tetrahedral geometry. Additionally, the thermal decomposition of complex 1 as well as its kinetic mechanisms and equations is studied under the non-isothermal integral and differential methods in air by TG-DTG curves.
文摘The thermal decomposition of 2-(4-methoxycarbonylphenyl)-5-nitryl-6-hydroxybenzoxazole(MNB) in N2 atmosphere was studied by thermogravimetry(TG) and differential thermogravimetry(DTG).It is a sequential process.The molecular bond orders were calculated by GAMESS method and the IR spectra of MNB and its intermediates in thermal decomposition at various temperatures were determined.The mechanism of the thermal decomposition has been discussed,the C-N bond breakdown and the nitro group elimination occurred in the initial step of the decomposition.The thermal decomposition kinetic parameters such as apparent activation energy E=115.5kJ·mol-1,pre-exponential factor A = 1.698×1010 min-1 and apparent reaction order n = 0 were obtained according to test data.