Two new Gd Ⅲ complexes with nitrilotriacetic acid(nta) and trans-1,2-cyclohexanediaminetetraacetic acid(Cydta) ligands were synthesized. Their crystal structures were determined by single-crystal X-ray structure anal...Two new Gd Ⅲ complexes with nitrilotriacetic acid(nta) and trans-1,2-cyclohexanediaminetetraacetic acid(Cydta) ligands were synthesized. Their crystal structures were determined by single-crystal X-ray structure analyses. The crystal data are as follows: K 3[Gd Ⅲ(nta) 2·(H 2O)]·6H 2O, monoclinic system, C2/c space group, a=1.534 81(15) nm, b=1.292 05(12) nm, c=2.610 8(3) nm, β=96.244(2)°, V=5.146 7(9) nm 3, Z=8, M=776.87, D c=2.005 g/cm 3, μ= 3.149 mm -1 and \{F(000)=\}3 080, R=0.024 5, wR=0.064 3 for 4 455 unique reflections and R= 0.028 9, wR=0.067 2 for all 10 305 reflections. The Gd ⅢN 2O 7 part in the [Gd Ⅲ(nta) 2(H 2O)] 3- anion is a pseudo-monocapped square antiprismatic nine-coordination structure.(NH 4)[Gd Ⅲ(Cydta)(H 2O) 2]·5H 2O, triclinic system, P1 space group, a=0.866 2(3) nm, b=1.006 7(3) nm, c= 1.444 8(5) nm, α= 88.282(5)°, β=75\^190(5)°, γ=88.317(4)°, V=1.217 2(7) nm 3, Z=2, M=643.69, D c=1.756 g/cm 3, μ=2.798 mm -1 and F(000)=650, R=0.030 3, wR=0.080 9 for 4 273 unique reflections and R=0.033 2, wR=0.082 5 for all 5 062 reflections. The Gd ⅢN 2O 6 part in the [Gd Ⅲ(Cydta)(H 2O) 2] - anion has a pseudo-square antiprismatic eight-coordination structure.展开更多
In this paper, the molecular and crystal structures of the NH4[Y(trans CYDTA)(H2O)2]· 4.5 H2O(trans CYDTA=trans 1,2 cyclohexanediaminetetraacetic acid) are reported. The crystal data are as follows: Triclinic sys...In this paper, the molecular and crystal structures of the NH4[Y(trans CYDTA)(H2O)2]· 4.5 H2O(trans CYDTA=trans 1,2 cyclohexanediaminetetraacetic acid) are reported. The crystal data are as follows: Triclinic system, space group,a=0.8599(6)nm,b=1.0021(7)nm,c=1.4370(9)nm,α =88.095(13)° ,β =75.559(1)° ,γ =88.344(12)° ,V=1.1981(14)nm3,Z=2, M=708.68,Dc=1.570g· cm- 3, μ =2.506mm- 1 and F(000)=590. The final R1 and wR2 are 0.0571 and 0.1350 for 4205 [I >2.0σ (I)] unique reflections and 0.1007 and 0.1615 for all 4981 reflections, respectively. In the title complex, the anion [Y(trans CYDTA)(H2O)2]- has an eight coordination structure with distorted square antiprism. The trans CYDTA which acts as a hexadentate ligand with four O atoms and two N atoms and two H2O molecules directly coordinate to central metal Y? ion. It can be known that the Y? ion can form an eight coordinate compound with aminopolycarboxylic acid ligands in addition nine coordination structure.展开更多
Synthesis and structure of the complex NH 4[Yb(Cydta) (H 2O) 2]·5H 2O(Cydta=trans 1,2 cyclohexanediaminetetraacetic acid) were reported. The crystal and molecular structures of the title complex were determ...Synthesis and structure of the complex NH 4[Yb(Cydta) (H 2O) 2]·5H 2O(Cydta=trans 1,2 cyclohexanediaminetetraacetic acid) were reported. The crystal and molecular structures of the title complex were determined by single crystal X ray structure analysis. The crystal of the complex NH 4[Yb Ⅲ(Cydta)(H 2O) 2]·5H 2O belongs to triclinic crystal system and P (1) space group. The crystal data are as follows: a =0.8584(4) nm, b =1.0040(4) nm, c =1.4418(6) nm, V =1.2025(9) nm 3, Z =2, M =659.49, D c=1.821 g·cm -3 , μ =3.963 mm -1 and F (000)=662. The final R and R w values for 4093 ( I >2 θ(I )) unique reflections are 0.0454 and 0.0927, and the R and R w values for 4877 (all data) are 0.0624 and 0.0985, respectively. The complex anion [Yb(Cydta)(H 2O) 2] - has a pseudo square antiprismatic eight coordinate structure in which the six coordinate atoms, two N and four O, are from a Cydta ligand and two water molecules coordinate to Yb(Ⅲ) ion directly as the another two ligands.展开更多
The crystal and molecular structures of cydta (trans-1, 2-cyclohexanediaminetetraacetic acid) have been determined by single\|crystal X-ray structure analyses. The reasons that RE Ⅲ -edta and RE Ⅲ -cydta compl...The crystal and molecular structures of cydta (trans-1, 2-cyclohexanediaminetetraacetic acid) have been determined by single\|crystal X-ray structure analyses. The reasons that RE Ⅲ -edta and RE Ⅲ -cydta complexes select different coordinate structures were discussed and illustrated through the comparison of the molecular and crystal structures between edta and cydta, (NH_ 4 )\[Y Ⅲ (edta)(H_ 2 O)_ 3 \]\55H_ 2 O and (NH_ 4 )\[Y Ⅲ (cydta)(H_ 2 O)_ 2 \]\55H_ 2 O as well as (NH_ 4 )\[Gd Ⅲ (edta)(H_ 2 O)_ 3 \]\55H_ 2 O and (NH_ 4 )\[Gd Ⅲ (cydta) (H_ 2 O) _ 2 \]\55H_ 2 O complexes.展开更多
The intramolecular process of Mg ( Ⅱ ) - , Sc ( Ⅲ ) - , Y ( Ⅲ ) - , In(Ⅲ)-and Pb ( Ⅱ )-trans-1,2-cyclohexanediaminetetraacetic acid (CyDTA) complexes was studied by the method of proton dynamic NMR(DNMR). The top...The intramolecular process of Mg ( Ⅱ ) - , Sc ( Ⅲ ) - , Y ( Ⅲ ) - , In(Ⅲ)-and Pb ( Ⅱ )-trans-1,2-cyclohexanediaminetetraacetic acid (CyDTA) complexes was studied by the method of proton dynamic NMR(DNMR). The top limit of. the experimental temperature range of deuterium oxide solutions was extended from 100℃ to 167 ℃ instead of the previous 100 ℃ by using sealed, thick-walled tubes to observe experimental phenomena further. It was found that another intramolecular process, i. e. B, R (Bonded State, Rotational State) conversion, exists in these complexes formed by polyaminepolycarboxylic ligands in addition to △,A conversion and nitrogen inversion. A quantitative treatment was proposed to estimate the relative populations of acetate groups in B and R states.展开更多
This standard specifies the method summary, reagents, apparatus, sampling, procedure, test results calculation and permissible tolerance of the determination of magnesium oxide by CyDTA volumetric method.
文摘Two new Gd Ⅲ complexes with nitrilotriacetic acid(nta) and trans-1,2-cyclohexanediaminetetraacetic acid(Cydta) ligands were synthesized. Their crystal structures were determined by single-crystal X-ray structure analyses. The crystal data are as follows: K 3[Gd Ⅲ(nta) 2·(H 2O)]·6H 2O, monoclinic system, C2/c space group, a=1.534 81(15) nm, b=1.292 05(12) nm, c=2.610 8(3) nm, β=96.244(2)°, V=5.146 7(9) nm 3, Z=8, M=776.87, D c=2.005 g/cm 3, μ= 3.149 mm -1 and \{F(000)=\}3 080, R=0.024 5, wR=0.064 3 for 4 455 unique reflections and R= 0.028 9, wR=0.067 2 for all 10 305 reflections. The Gd ⅢN 2O 7 part in the [Gd Ⅲ(nta) 2(H 2O)] 3- anion is a pseudo-monocapped square antiprismatic nine-coordination structure.(NH 4)[Gd Ⅲ(Cydta)(H 2O) 2]·5H 2O, triclinic system, P1 space group, a=0.866 2(3) nm, b=1.006 7(3) nm, c= 1.444 8(5) nm, α= 88.282(5)°, β=75\^190(5)°, γ=88.317(4)°, V=1.217 2(7) nm 3, Z=2, M=643.69, D c=1.756 g/cm 3, μ=2.798 mm -1 and F(000)=650, R=0.030 3, wR=0.080 9 for 4 273 unique reflections and R=0.033 2, wR=0.082 5 for all 5 062 reflections. The Gd ⅢN 2O 6 part in the [Gd Ⅲ(Cydta)(H 2O) 2] - anion has a pseudo-square antiprismatic eight-coordination structure.
文摘In this paper, the molecular and crystal structures of the NH4[Y(trans CYDTA)(H2O)2]· 4.5 H2O(trans CYDTA=trans 1,2 cyclohexanediaminetetraacetic acid) are reported. The crystal data are as follows: Triclinic system, space group,a=0.8599(6)nm,b=1.0021(7)nm,c=1.4370(9)nm,α =88.095(13)° ,β =75.559(1)° ,γ =88.344(12)° ,V=1.1981(14)nm3,Z=2, M=708.68,Dc=1.570g· cm- 3, μ =2.506mm- 1 and F(000)=590. The final R1 and wR2 are 0.0571 and 0.1350 for 4205 [I >2.0σ (I)] unique reflections and 0.1007 and 0.1615 for all 4981 reflections, respectively. In the title complex, the anion [Y(trans CYDTA)(H2O)2]- has an eight coordination structure with distorted square antiprism. The trans CYDTA which acts as a hexadentate ligand with four O atoms and two N atoms and two H2O molecules directly coordinate to central metal Y? ion. It can be known that the Y? ion can form an eight coordinate compound with aminopolycarboxylic acid ligands in addition nine coordination structure.
文摘Synthesis and structure of the complex NH 4[Yb(Cydta) (H 2O) 2]·5H 2O(Cydta=trans 1,2 cyclohexanediaminetetraacetic acid) were reported. The crystal and molecular structures of the title complex were determined by single crystal X ray structure analysis. The crystal of the complex NH 4[Yb Ⅲ(Cydta)(H 2O) 2]·5H 2O belongs to triclinic crystal system and P (1) space group. The crystal data are as follows: a =0.8584(4) nm, b =1.0040(4) nm, c =1.4418(6) nm, V =1.2025(9) nm 3, Z =2, M =659.49, D c=1.821 g·cm -3 , μ =3.963 mm -1 and F (000)=662. The final R and R w values for 4093 ( I >2 θ(I )) unique reflections are 0.0454 and 0.0927, and the R and R w values for 4877 (all data) are 0.0624 and 0.0985, respectively. The complex anion [Yb(Cydta)(H 2O) 2] - has a pseudo square antiprismatic eight coordinate structure in which the six coordinate atoms, two N and four O, are from a Cydta ligand and two water molecules coordinate to Yb(Ⅲ) ion directly as the another two ligands.
文摘The crystal and molecular structures of cydta (trans-1, 2-cyclohexanediaminetetraacetic acid) have been determined by single\|crystal X-ray structure analyses. The reasons that RE Ⅲ -edta and RE Ⅲ -cydta complexes select different coordinate structures were discussed and illustrated through the comparison of the molecular and crystal structures between edta and cydta, (NH_ 4 )\[Y Ⅲ (edta)(H_ 2 O)_ 3 \]\55H_ 2 O and (NH_ 4 )\[Y Ⅲ (cydta)(H_ 2 O)_ 2 \]\55H_ 2 O as well as (NH_ 4 )\[Gd Ⅲ (edta)(H_ 2 O)_ 3 \]\55H_ 2 O and (NH_ 4 )\[Gd Ⅲ (cydta) (H_ 2 O) _ 2 \]\55H_ 2 O complexes.
基金Supported by the National Natural Science Foundation of China
文摘The intramolecular process of Mg ( Ⅱ ) - , Sc ( Ⅲ ) - , Y ( Ⅲ ) - , In(Ⅲ)-and Pb ( Ⅱ )-trans-1,2-cyclohexanediaminetetraacetic acid (CyDTA) complexes was studied by the method of proton dynamic NMR(DNMR). The top limit of. the experimental temperature range of deuterium oxide solutions was extended from 100℃ to 167 ℃ instead of the previous 100 ℃ by using sealed, thick-walled tubes to observe experimental phenomena further. It was found that another intramolecular process, i. e. B, R (Bonded State, Rotational State) conversion, exists in these complexes formed by polyaminepolycarboxylic ligands in addition to △,A conversion and nitrogen inversion. A quantitative treatment was proposed to estimate the relative populations of acetate groups in B and R states.
文摘This standard specifies the method summary, reagents, apparatus, sampling, procedure, test results calculation and permissible tolerance of the determination of magnesium oxide by CyDTA volumetric method.
