Synthesis and Structural Characterization of ... - Jacobs University

Chapter 5
Published Results
The pentatungstate {W 5 } unit can be considered as an assembly comprising two types of
building blocks (see Figure 5.6):
- One tritungstate {W 3 } fragment (green in Figure 5.6) made of three edge-shared
[WO 6 ] octahedra connected through four μ 2 -oxo bridges. This {W 3 } fragment differs
significantly from the {W 3 } fragment present in polyanion 26 since it lacks the μ 3 -oxo
bridge which is responsible for the C 3 symmetry in each of the well- known “Keggin”
triads.
- One ditungstate {W 2 } subunit (red in Figure 5.6) composed of two edge-shared [WO 6 ]
octahedra linked to the {W 3 } fragment through two μ 2 -oxo bridges and one μ 3 -oxo
bridge.
{W 5 } subunit
Polyanion 27
Figure 5.6. Polyhedral representations of the {TeW 15 } and the basic building-block unit {W 5 }
of (27). The color code is as follows: W 3 (green), W 2 (red), Te (blue). The two subunits were
colored differently for clarification.
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