Synthesis and Structural Characterization of ... - Jacobs University

Chapter 1
Introduction
The lanthanum-containing Wells–Dawson dimer [{La(CH 3 COO)(H 2 O) 2 (α 2 -P 2 W 17 O 61 )} 2 ] 16−
which consists of two monolacunary Wells–Dawson α 2 -P 2 W 17 fragments connected by a
lanthanum-acetate dimer, (La 2 (CH 3 COO)(H 2 O) 4 ) 4+ has been reported. Each La 3+ ion is ninecoordinated
in a monocapped, square-antiprismatic fashion (Figure 1.14). 52b
Figure 1.14 Combined polyhedral/ball-and-stick representation of [{La(CH 3 COO)(H 2 O) 2 (α 2 -
P 2 W 17 O 61 )} 2 ] 16− . Red octahedra: WO 6 , green balls: P, blue balls: La, grey balls: C, red balls:
O. No hydrogen atoms shown.
The monolanthanide-containing polyanion family [Ln(β 2 -SiW 11 O 39 ) 2 ] 13− (Ln = La, Ce, Sm,
Eu, Gd, Tb, Yb, Lu) has also been synthesized and structurally characterized. These
polyanions are composed of two chiral (β 2 -SiW 11 O 39 ) units sandwiching the Ln 3+ ion (Figure
1.15). 52c
Figure 1.15 Combined polyhedral/ball-and-stick representation of [Ln(β 2 -SiW 11 O 39 ) 2 ] 13− . Red
and yellow octahedra: WO 6 , green balls: silicon, blue balls: lanthanide, the rotated triad was
colored yellow for clarification.
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