稀土离子与2,9-二甲基-1,10-菲罗啉的α-氨甲基吡啶衍生物的二元配合物的稳定性研究

Stability of Rare Earth Ion-N,N′-bis(2′-Pyridine)methyl-1,10-Phenanthroline-2,9-Dimethanamine Binary Complexes

在25 0±0.1℃,0.1mol·L-3NaClO4的条件下,用pH电位滴定法测定了配体2,9 二甲基 1,10 菲罗啉的α 氨甲基吡啶衍生物 N,N′ 二 α 吡啶甲基 1,10 菲罗啉 2,9 二甲胺(L)在水溶液中分别与稀土离子Ln(Ln=La3+,Ce3+,Pr3+,Nd3+,Sm3+,Eu3+,Gd3+,Tb3+,Dy3+,Ho3+)的二元配合物的稳定常数。提出了配合物在溶液中的可能结构。对金属离子对配合物稳定性的影响进行了详细的讨论,并比较讨论了稀土离子和其它金属离子如Co2+,Ni2+,Cu2+等与配体L的所形成配合物的稳定性差异的原因。运用线性回归,对有放射性的Pm3+与相应配体的二元配合物的稳定常数进行了推测。

The stability constants of binary complexes Ln-L (Ln=La^(3+), Ce^(3+), Pr^(3+), Nd^(3+), Sm^(3+), Eu^(3+), Gd^(3+), Tb^(3+), Dy^(3+), Ho^(3+), L=N, N′-bis(2′-pyridine)methyl-1,10-phenanthroline-2,9-dimethanamine) were determined by pH potentiometric titration method at 25±0.1 ℃, 0.1 mol·L^(-1) NaClO_4. The probable structures of the corresponding complexes were proposed. The influence of the metal ions to the stability of binary complexes and the stability difference between the complexes of rare earth ion and the corresponding complexes of Co^(2+), Ni^(2+), Cu^(2+) ions were discussed. The stability constants of the corresponding binary complex of radioactive Pm^(3+) ion are estimated by linear regression.