Two new octadecanuclear copper(II)-lanthanide(III) clusters encapsulationg #mu#_9-NO_3~- anions. Synthesis, structures, and magnetic properties of [Cu_(12)Ln_6(#mu#_3-OH)_(24)(C_5H_5NCH_2CO_2)_(12)(H_2O)_(18)(#mu#_9-NO_3)](PF_6)_(10)(NO_3)_7·12H_2O

摘要

Two new octadecanuclear cluters [Cu_(12)Ln_6(#mu#_3-OH)_(24)(C_5H_5NCH_2CO_2)_(12)(H_2O)_(18)(#mu#_9-NO_3)](PF_6)_(10)(NO_3)_7·12H_2O [(Ln~(III) = Sm~(III) (1) or Gd~(III) (2)] have been synthesized and characterized by X-ray diffraction. They are isomorphous and crystallize in the triclinic space group P1 with Z = 1. The cell dimensions of 1 are a = 17.366(1), b = 17.790(1), and c = 19.002(1) A, #alpha# = 117.279(1), #beta# = 91.763(1), and #gamma# = 111.585(1) deg. In the cluster, 6 Sm~(III) atoms are positioned at the vertices of an octahedron, while 12 Cu~(II) atoms are at the midpoints of the edges of the octahedron. The Cu~(II)-Sm~(III) metal framework is interconnected by the 24 similar #mu#_3-OH~- groups, each bridging one Sm~(III) and two Cu~(II) atoms. The octahedral cage encapsulates an unusual #mu#_9-NO_3~- anion with each oxygen atom coordinated to three Cu~(II) atoms. The 12 carboxylate ligands act as as #mu#_2-carboxylate-counteranion plyas an important role in crystallization of the two complexes.