Synthesis, Structure and Catalytic Activity of ... - Jacobs University

Ch.1 Introduction
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Fig. 1.13 Polyhedral representation of [{Ti3P2W15O57.5(OH)3}4] 24- tetramer, color code: WO6
octahedra (red), PO4 tetrahedra (green), titanium (yellow), oxygen (red balls)
In 2004, the [{β-Ti2SiW10O39}4] 24- (Fig. 1.14) cyclic tetramer was reported, it is
formed by interaction of the solid TiO(SO4) with the dilacunary Keggin [γ-
SiW10O36] 8- which undergoes rotation to form the β-isomer. 35
And lately, the new structure of [Ti2(OH)2As2W19O67 (H2O)] 8- (Fig. 1.15) was
reported and characterized in the solid state by single-crystal XRD, IR,
elemental analysis and TGA. Solution studies involving UVspectrophotometry
and electrochemistry were also performed in addition to a
study on the cyclohexene system having the tetra-butyl ammonium TBA salt
of the anion as an oxidation catalyst, 43 followed by a more detailed study
concerning the influence of the proton content of this catalyst over its
performance. 46
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