In this paper protonation constants of the title lisand and stability constants of its coordination compounds with rare earths have been determined by potentiometric titration at 25±0.1℃ and ionic strength of 0....In this paper protonation constants of the title lisand and stability constants of its coordination compounds with rare earths have been determined by potentiometric titration at 25±0.1℃ and ionic strength of 0.10mol.dm^(-3)NaClO_4. The coordination of rare earths with DL-alanyl-alanine has been discussed. The stability of the coordination compound shows 'tetrad effect'. The position for yttrium shifts from its usual Bo-Er region to the vicinity of Tb.展开更多
In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2 (HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IR spectra.The title compound crystal...In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2 (HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IR spectra.The title compound crystallizes in triclinic,space.group P with a=9.148(1),b=11.460(2), c=13.506(2);α=112.76(1),β=91.83(1),γ=91.99(1)°;Z=1;V=1303.3.The final R factor is 0.0235.The rare earth ion is nine-coordinated to form a distorted monocapped square antiprism.展开更多
Much work has been done on the study of the coordination compounds formed by the reaction of rare earth salts with amino acids. In this note, we report the preparation and characterization of the coordination compound...Much work has been done on the study of the coordination compounds formed by the reaction of rare earth salts with amino acids. In this note, we report the preparation and characterization of the coordination compounds formed by the nitrates of 13 trivalent lanthanides with alanine, which have not yet been found in literature now.展开更多
p-Methoxybenzoyl-benzoylmethane(HA)and its complexes LnA_4QH and LnA_3·xH_2O(for Ln=La～ Yb,Q=n-tributyl amine,diethyl amine,hexahydropyridine)were synthesized and characterized by elemental analysis,molar conduc...p-Methoxybenzoyl-benzoylmethane(HA)and its complexes LnA_4QH and LnA_3·xH_2O(for Ln=La～ Yb,Q=n-tributyl amine,diethyl amine,hexahydropyridine)were synthesized and characterized by elemental analysis,molar conductivity measurement,infrared spectroscopy,UV-visible absorption spectroscopy,thermal analysis and ~1H NMR spectra.Possibilities of using praseodymium and europium complexes as shift reagent are also discussed.展开更多
Two coordination compounds of rare earth perchlorates with alanine and imidazole, [RE(Ala)n(Im)(H2O)]- (ClO4)3(s) (RE=La, n=3; RE=Nd, n=2), have been prepared and characterized. The standard molar enthalpies of reacti...Two coordination compounds of rare earth perchlorates with alanine and imidazole, [RE(Ala)n(Im)(H2O)]- (ClO4)3(s) (RE=La, n=3; RE=Nd, n=2), have been prepared and characterized. The standard molar enthalpies of reaction for the following two reactions, LaCl37H2O(s)+3Ala(s)+Im(s)+3NaClO4(s)=[La(Ala)3(Im)(H2O)]- (ClO4)3(s)+3NaCl(s)+6H2O(l) (1) and NdCl36H2O(s)+2Ala(s)+Im(s)+3NaClO4(s)=[Nd(Ala)2(Im)(H2O)]- (ClO4)3(s)+3NaCl(s)+5H2O(l) (2), were determined by solution-reaction calorimetry, at T=298.15 K, as 36.168±0.642 kJmol-1 and 48.590±0.934 kJmol-1 respectively. From the results and other auxiliary quantities, the standard molar enthalpies of formation of [La(Ala)3(Im)(H2O)](ClO4)3(s) and [Nd(Ala)2(Im)(H2O)] (ClO4)3(s) were derived, fmHD!{[La(Ala)3(Im)(H2O)](ClO4)3, s}=(-2984.8±1.0) kJmol-1 and fmHD! {[Nd(Ala)2(Im)(H2O)]- (ClO4)3, s}=(-2387.8±0.8) kJmol-1 , respectively.展开更多
Ring opening polymerization of propylene sulfide using rare earth coordination catalysts has been investigated for the first time. It has been found that trinary rare earth coordination catslysts composed of rare eart...Ring opening polymerization of propylene sulfide using rare earth coordination catalysts has been investigated for the first time. It has been found that trinary rare earth coordination catslysts composed of rare earth compounds of phosphonate, naphthenate or acetylacetonate, trialkyl sluminum and water are effective catalysts for the polymerization of propylene sulfide. The polymerization in toluene is a homogeneous reaction. High molecular weight as high as several million poly(propylene sulfide) with high yield can be prepared by these catalysts. Kinetic studies showed that the polymerization rate is of first order with respect to both monomer concentration and catalyst concentration. The activation energy of the polymerization reaction is 61.4 k fJ/mol. The structure of the polymers so obtained has also been characterized by ^(13)C NMR spectroscopy, X-ray diffraction, gel permeation chromatography and differential scanning calorimetry.展开更多
A new method is proposed for determining the composition and stability constant of coordination compounds of the form M m R n ; it can be used to differentiate mono and poly nuclear coordination compounds. ...A new method is proposed for determining the composition and stability constant of coordination compounds of the form M m R n ; it can be used to differentiate mono and poly nuclear coordination compounds. The equation derived is lg( A i/(A max - A i) m)=n lg c′ R+lg( m·β(c M/A max ) ( m -1) ). The method is based on Bent French limited logarithm method. The demonstration of the proposed method has yielded correct results for Sc 3+ chlorophosphonazo Ⅲ system and Fe 3+ Chromazurol S system.展开更多
A new coordination compound, [{Nd(NMP)_2(H_2O)_6Cl}{Nd(NMP)_2(H_2O)_7}H (P_2Mo_(18)O_(62)) (NMP=N-methyl-2-pyrrolidone) was synthesized and characterized by elemental analyses, IR spectrum, and X-ray single crystal st...A new coordination compound, [{Nd(NMP)_2(H_2O)_6Cl}{Nd(NMP)_2(H_2O)_7}H (P_2Mo_(18)O_(62)) (NMP=N-methyl-2-pyrrolidone) was synthesized and characterized by elemental analyses, IR spectrum, and X-ray single crystal structural analysis. The crystal structure indicates that the title compound belongs to monoclinic space group C _c, with unit cell dimensions a =2.4528(5) nm, b =1.9495(4) nm, c =2.4405(5) nm, β =109.94(3)°, Z =4, V =10.970 (4) nm^3, D _c=2.262 g·cm^(-3), R 1=0.0676, wR 2=0.1441. The ESR spectrum of powder of the title compound at 110 K after being exposed to sunlight shows the signal of Mo^(5+), g =1.95. Cyclic voltammetry was measured in aqueous solution containing 0.1 mol·L^(-1) KCl as the supporting electrolyte and shows that the title compound undergoes two one-electron reversible reductions.展开更多
文摘In this paper protonation constants of the title lisand and stability constants of its coordination compounds with rare earths have been determined by potentiometric titration at 25±0.1℃ and ionic strength of 0.10mol.dm^(-3)NaClO_4. The coordination of rare earths with DL-alanyl-alanine has been discussed. The stability of the coordination compound shows 'tetrad effect'. The position for yttrium shifts from its usual Bo-Er region to the vicinity of Tb.
文摘In this paper,a new rare earth benzoate coordination compound,[TbL_3(HL)(H_2O)]_2 (HL=C_7H_6O_2=benzoic acid) is synthesized and characterized by elemental analysis DTA,TG,DTC,and IR spectra.The title compound crystallizes in triclinic,space.group P with a=9.148(1),b=11.460(2), c=13.506(2);α=112.76(1),β=91.83(1),γ=91.99(1)°;Z=1;V=1303.3.The final R factor is 0.0235.The rare earth ion is nine-coordinated to form a distorted monocapped square antiprism.
基金Project supported by the National Natural Science Foundation of China.
文摘Much work has been done on the study of the coordination compounds formed by the reaction of rare earth salts with amino acids. In this note, we report the preparation and characterization of the coordination compounds formed by the nitrates of 13 trivalent lanthanides with alanine, which have not yet been found in literature now.
基金This Project was supported by the National Natural Science Foundation of China
文摘p-Methoxybenzoyl-benzoylmethane(HA)and its complexes LnA_4QH and LnA_3·xH_2O(for Ln=La～ Yb,Q=n-tributyl amine,diethyl amine,hexahydropyridine)were synthesized and characterized by elemental analysis,molar conductivity measurement,infrared spectroscopy,UV-visible absorption spectroscopy,thermal analysis and ~1H NMR spectra.Possibilities of using praseodymium and europium complexes as shift reagent are also discussed.
基金Project supported by the Teaching and Research Award Program for Outstanding Young Professors in High Education Institute Ministry of Educa-tion China.
文摘Two coordination compounds of rare earth perchlorates with alanine and imidazole, [RE(Ala)n(Im)(H2O)]- (ClO4)3(s) (RE=La, n=3; RE=Nd, n=2), have been prepared and characterized. The standard molar enthalpies of reaction for the following two reactions, LaCl37H2O(s)+3Ala(s)+Im(s)+3NaClO4(s)=[La(Ala)3(Im)(H2O)]- (ClO4)3(s)+3NaCl(s)+6H2O(l) (1) and NdCl36H2O(s)+2Ala(s)+Im(s)+3NaClO4(s)=[Nd(Ala)2(Im)(H2O)]- (ClO4)3(s)+3NaCl(s)+5H2O(l) (2), were determined by solution-reaction calorimetry, at T=298.15 K, as 36.168±0.642 kJmol-1 and 48.590±0.934 kJmol-1 respectively. From the results and other auxiliary quantities, the standard molar enthalpies of formation of [La(Ala)3(Im)(H2O)](ClO4)3(s) and [Nd(Ala)2(Im)(H2O)] (ClO4)3(s) were derived, fmHD!{[La(Ala)3(Im)(H2O)](ClO4)3, s}=(-2984.8±1.0) kJmol-1 and fmHD! {[Nd(Ala)2(Im)(H2O)]- (ClO4)3, s}=(-2387.8±0.8) kJmol-1 , respectively.
基金Project supported by the National Natural Science Foundation of Chins, the National Education Commission of China and Chinese Petrochemical Corporation.
文摘Ring opening polymerization of propylene sulfide using rare earth coordination catalysts has been investigated for the first time. It has been found that trinary rare earth coordination catslysts composed of rare earth compounds of phosphonate, naphthenate or acetylacetonate, trialkyl sluminum and water are effective catalysts for the polymerization of propylene sulfide. The polymerization in toluene is a homogeneous reaction. High molecular weight as high as several million poly(propylene sulfide) with high yield can be prepared by these catalysts. Kinetic studies showed that the polymerization rate is of first order with respect to both monomer concentration and catalyst concentration. The activation energy of the polymerization reaction is 61.4 k fJ/mol. The structure of the polymers so obtained has also been characterized by ^(13)C NMR spectroscopy, X-ray diffraction, gel permeation chromatography and differential scanning calorimetry.
文摘A new method is proposed for determining the composition and stability constant of coordination compounds of the form M m R n ; it can be used to differentiate mono and poly nuclear coordination compounds. The equation derived is lg( A i/(A max - A i) m)=n lg c′ R+lg( m·β(c M/A max ) ( m -1) ). The method is based on Bent French limited logarithm method. The demonstration of the proposed method has yielded correct results for Sc 3+ chlorophosphonazo Ⅲ system and Fe 3+ Chromazurol S system.
文摘A new coordination compound, [{Nd(NMP)_2(H_2O)_6Cl}{Nd(NMP)_2(H_2O)_7}H (P_2Mo_(18)O_(62)) (NMP=N-methyl-2-pyrrolidone) was synthesized and characterized by elemental analyses, IR spectrum, and X-ray single crystal structural analysis. The crystal structure indicates that the title compound belongs to monoclinic space group C _c, with unit cell dimensions a =2.4528(5) nm, b =1.9495(4) nm, c =2.4405(5) nm, β =109.94(3)°, Z =4, V =10.970 (4) nm^3, D _c=2.262 g·cm^(-3), R 1=0.0676, wR 2=0.1441. The ESR spectrum of powder of the title compound at 110 K after being exposed to sunlight shows the signal of Mo^(5+), g =1.95. Cyclic voltammetry was measured in aqueous solution containing 0.1 mol·L^(-1) KCl as the supporting electrolyte and shows that the title compound undergoes two one-electron reversible reductions.
