Publications by authors named "Ekkehard Diemann"

The solution behavior of the largest inorganic acid known thus far, the neutral, spherical iron/molybdenum/oxide nanocluster {Mo72Fe30} ([triple bond{(MoVI) MoVI5}12FeIII30 1a), including the pH-controlled deprotonation, is reported. The acidic properties are due to the 30 peripheral, weakly acidic FeIII(H2O) groups that form a unique Archimedean solid with all edges and dihedral angles being equal, the icosidodecahedron, and therefore an "isotropic" surface. Interestingly, the aqueous solutions are stable even for months because of the inertness of the spherical solutes and the presence of the hard FeIII and MoVI centers.

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Surfactants and membrane lipids readily assemble into complex structures such as micelles, liposomes or hollow vesicles owing to their amphiphilic character-the fact that part of their structure is attracted to polar environments while another part is attracted to non-polar environments. The self-assembly of complex structures also occurs in polyoxometallate chemistry, as exemplified by the molybdenum blue solutions known for centuries. But while the presence of nanometre-sized metal oxide aggregates in these solutions has long been recognized, unravelling the composition and formation process of these aggregates proved difficult.

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In context with the challenge to assemble giant molecules into patterns with limited size, molybdenum oxide giant spheres (with a molecular mass of about 16 kDa) could be 'kicked out' like soccer balls into the gas phase using matrix assisted laser desorption and ionization (MALDI) and detected by TOF mass spectrometry while cluster collectives ranging from dimers to pentamers were observed.

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