Chapter 4 - Jacobs University

system, space group I4/m, unit cell parameters a = b = 26.753(3) Å, c = 21.241(3) Å, and Z =
2. 1a was also characterized by FTIR spectroscopy, elemental analysis, electrochemistry,
scanning tunneling microscopy (STM), dynamic light scattering (DLS), magnetism and 31 P
NMR. Polyanion 1 exhibits a singlet at d = -29.3 ppm in 31 P NMR indicating that all eight
phosphorus atoms are equivalent, in complete agreement with the solid-state structure.
Chapter 4 describes a sixteen iron containing polyanion [P 8 W 48 O 184 Fe 16 (OH) 28 (H 2 O) 4 ] 20-
(2), which has been synthesized by reaction of different iron species containing Fe 2+ (in presence
of O 2 ) or Fe 3+ ions with P 8 W 48 in aqueous, acidic medium (pH ~4). Polyanion 2 contains—in
the form of a cyclic arrangement—the unprecedented {Fe 16 (OH) 28 (H 2 O) 4 } 20+ nanocluster, with
16 edge- and corner-sharing FeO 6 octahedra, grafted on the inner surface of the crown-shaped
P 8 W 48 precursor. Polyanion 2 was isolated as the mixed cation salts
Li 4 K 16 [P 8 W 48 O 184 Fe 16 (OH) 28 (H 2 O) 4 ]∙66H 2 O∙2KCl (2a) and
Na 9 K 11 [P 8 W 48 O 184 Fe 16 (OH) 28 (H 2 O) 4 ]∙100H 2 O (2b) which crystallized in the orthorhombic space
group Pnnm, a = 36.3777(9) Å, b = 13.9708(3) Å, c = 26.9140(7) Å, and Z = 2) ( 2a) and in the
monoclinic space group C2/c, a = 46.552(4) Å, b = 20.8239(18) Å, c = 27.826(2) Å, β =
97.141(2)° and Z = 4 (2b), respectively. Compounds 2a and 2b were also characterized by FTIR
and ESR spectroscopy, TGA, elemental analysis, electrochemistry as well as susceptibility
measurements.
Chapter 5 describes the new organoruthanium polyanion [{K(H 2 O)} 3 {Ru(pcymene)(H
2 O)} 4 P 8 W 49 O 186 (H 2 O) 2 ] 27- (3), which was prepared by a one-pot reaction of [Ru(pcymene)Cl
2 ] 2 with P 8 W 48 (10:1 ratio) in aqueous 1M LiOAc/CH 3 COOH buffer solution at pH
6.0. Polyanion 3 has four {Ru(p-cymene)(H 2 O)} 2+ fragments grafted onto the cyclic P 8 W 48
precursor and it contains one extra WO 6 group resulting in an unprecedented “P 8 W 49 ” assembly.
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