Synthesis and Structural Characterization of ... - Jacobs University

Chapter 1
Introduction
1.7.2 Lanthanide‐containing heteropolytungstates
To date, heteropolyanions are the most reported of the known lanthanide-containing POMs. In
recent years, there has been an increase in the number of lanthanide-containing
heteropolyoxotungstates. Here we review some examples of lanthanide-containing
heteropolytungstates which include discrete molecular species as well as 1-, 2- and 3-D
solid-state assemblies. For a detailed survey, Pope and Kortz groups have recently reported
reviews presenting lanthanide-containing POMs, the former reviewed this field in a
comprehensive fashion and the latter the recent example of polyoxotungstates. 30,41
Peacock and Weakley reported sandwich type silicotungstates containing lanthanides, of
general formula [Ln(SiW 11 O 39 ) 2 ] 13− . 31a Pope et al. reported one-dimensional chains of
lanthanide-containing monolacunary silicotungstates, the lanthanides being the linkers
between the different chain elements. 42 Xu et al. also reported similar extended structures
forming not only one-dimensional chain structures but also two-dimensional layers via
potassium cations. 43 The Pope group reported lanthanide derivatives of the Preyssler anion
[Na(H 2 O)P 5 W 30 O 110 ] 14− in which Ln 3+ replaced the internal Na + atom. 44 Also, Wang et al.
reported four extended phosphotungstate structures built from the Preyssler anion and
lanthanide linkers to form one-dimensional chains. 45 Polymeric large molecular
polyoxoanions were demonstrated by Francesconi’s europium-containing phosphotungstate
[(PEu 2 W 10 O 38 ) 4 (W 3 O 14 )] 30− , and by Gouzerh’s
[(SbW 9 O 33 ) 4 {WO 2 (H 2 O)} 2 Ce 3 (H 2 O) 8 (Sb 4 O 4 )] 19− . 46,47 Also, Fukaya and Yamase reported two
crown-shaped, europium-containing tungstoarsenates(III), [K{Eu(H 2 O) 2 (α-AsW 9 O 33 )} 6 ] 35−
and [Cs{Eu(H 2 O) 2 (α-AsW 9 O 33 )} 4 ] 23− . 46−48 Recently, Pope et al. synthesized
[KP 8 W 48 O 184 (H 4 W 4 O 12 ) 2 Ln 2 (H 2 O) 10 ] 25− by the reaction of [P 8 W 48 O 184 ] 40− with lanthanide
cations resulting in 3D networks. 49 Patzke et al. has very recently reported the synthesis and
structure of the octa-gadolinium(III)-containing 124-tungsto-12-arsenate(III)
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