Lanthanide contraction effect on crystal structures of lanthanide coordination polymers with cyclohexanocucurbit[6]uril ligand

作者：Zheng, Li-Mei; Liu, Jing-Xin^*

来源：Journal of Solid State Chemistry, 2017, 245: 45-49.

DOI：10.1016/j.jssc.2016.10.008

• Coordination polymer
• Cyclohexanocucurbit[6]uril
• Lanthanide (III) ions
• Lanthanide constraction

A series of compounds based on the macrocyclic ligand cyclohexanocucurbit[6]uril (Cy6Q[6]) with formulas {Ln(H2O)(6)Cy(6)Q[6]}center dot 2(CdCl4)center dot H3O center dot xH(2)O [isomorphous with Ln=La (1), Ce (2), Pr (3) and Nd (4), x=11 (1), 11 (2), 10 (3) and 11 (4)], {Sm(H2O)(5)Cy(6)Q[6])center dot 2(CdCl4)center dot H3O center dot 10H(2)O (5) and {Ln(H2O)(3)(NO3)@CY6Q[6]}2(CdCl4)center dot 2H(3)O center dot xH(2)O [isomorphous with Ln=Gd (6), Tb (7) and Dy (8), x=8 (6), 6 (7) and 6 (8)], have been successfully synthesized by the self-assembly of Cy6Q[6] with the corresponding lanthanide nitrate under hydrochloric acid aqueous solution in the presence of CdCl2. Single-crystal X-ray diffraction analyses revealed that compounds 1-8 all crystallize in monoclinic space group P2(1)/c, and display 1D coordination polymer structures. The lanthanide contraction effect on the structures of 1-8 has also been investigated and discussed in detail. In contrast, the reaction of Cy6Q[6] with the Ho(NO)(3), Tm(NO)(3), Yb(NO)(3) under the same conditions resulted in the compounds 9-11 with formulas Cy6Q[6]center dot 2(CdCl4)center dot 2H(3)O center dot xH(2)O [isomorphous with x=10 (9), 10 (10), and 9 (11)], in which no lanthanide cations are observed. The structural difference of these compounds indicates that the Cy6Q[6] may be used in the separation of lanthanide cations.

• 出版日期2017-1
• 单位安徽工业大学; 河南工业大学