Synthesis and Structural Characterization of ... - Jacobs University

Chapter 3
Published Results
tetrahedral hetero group. The claw-shaped [As 2 W 19 O 67 (H 2 O)] 14−
(As 2 W 19 ) precursor is a
member of this subclass, and its structure can be rationalized as two [B-α-AsW 9 O 33 ] 9− (AsW 9 )
units linked through a WO 6 group via four equatorial W-O-W bonds and two trans-related
terminal oxo and aqua ligands (see Figure 3.19). The dilacunary As 2 W 19 was first reported by
Tourné et al. in 1973, 7 and its structure was confirmed later by our group using single-crystal
X-ray diffraction. 8
Figure 3.19. Ball-and-stick representation of the dilacunary polyanion precursor
[As 2 W 19 O 67 (H 2 O)] 14− (As 2 W 19 ). The color code is as follows: W (black), As (yellow), H 2 O
(pink), O (red).
Incorporation of an additional W-bridge in the dilacunary As 2 W 19 unit results in the
monolacunary [As 2 W 20 O 68 (H 2 O)] 10− (As 2 W 20 ), which was first reported by Hervé and
coworkers (see Figure 3.20). 9 Interaction of As 2 W 19 with di- and trivalent transition metal and
main group elements has been investigated by different groups and has resulted in the
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