Synthesis and characterization of new families of lanthanide perrhenate complexes

Abstract

The synthesis, structures, and characterization of two new families of trivalent lanthanide perrhenate complexes, [Ln(ReO4)(H2O)4Cl]Cl·H2O (Ln ​= ​La – Nd) (1) and [Ln(ReO4)3(H2O)2] (Ln ​= ​Tb, Ho, Er) (2), along with the expansion of a third known family, [Ln(ReO4)3(H2O)4] (Ln ​= ​Tm, Lu, Y) (3), is presented. Complex 1 is a purely inorganic member of a rare class of compounds known as cationic materials. Single crystal X-ray diffraction analysis reveals that 1 crystallizes in the P21/m space group and is comprised of two-dimensional (2D) sheets constructed from LnO4(H2O)4Cl monocapped square antiprismatic (CN ​= ​9) lanthanide cations, 2 crystallizes in the C2 space group and is a three-dimensional (3D) structure constructed from two crystallographically unique LnO6(H2O)2 square antiprismatic (CN ​= ​8) lanthanide cations, and 3 crystallizes in the P21/n space group and is comprised of one-dimensional chains constructed from LnO4(H2O)4 square antiprismatic (CN ​= ​8) lanthanide cations. This work provides a comprehensive study on essentially the entire lanthanide series (sans Pm) and its complexation with perrhenate at room temperature. The structural features of these complexes exhibit properties influenced by contracting ionic radii and increasing Pearson hardness upon traversing the lanthanide series.