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Thorium metal centres

The cyclometallation of 2,6-di-/er/-butylphenoxide ligands at thorium(iv) metal centres can also be facile. Hence thermolysis of the dialkyls [Th(OC6H3Bu2-2,6)2(CH2SiMe3)2] and [Cp Th(OC6H3Bu2-2,6)(CH2SiMe3)2] leads to the corresponding mono-cyclometallated species (the latter structurally characterized as the PhsPO adduct) and one equivalent of TMS. " ... [Pg.481]

Relevant material on thorium is contained in articles on C-H activation and lanthanides in organic synthesis. Two mechanisms for H-H and C-H bond activations at d metal centres, in particular... [Pg.230]

Compounds with Sc, Y, lanthanoids and actinoids are of three types. Those with composition ME have the (6-coordinated) NaCl structure, whereas M3E4 (and sometimes M4E3) adopt the body-centred thorium phosphide structure (Th3P4) with 8-coordinated M, and ME2 are like ThAsi in which each Th has 9 As neighbours. Most of these compounds are metallic and those of uranium are magnetically ordered. Full details of the structures and properties of the several hundred other transition metal-Group 15 element compounds fall outside the scope of this treatment, but three particularly important structure types should be mentioned because of their widespread occurrence and relation to other structure types, namely C0AS3,... [Pg.555]

The four compounds with R = H are isostructural, and in the thorium complex the eight-coordinate metal atom lies at the centre of a distorted square antiprismatic array of four N and four O atoms. In benzene solution, however, the molecular weights of the complexes with R = H indicate that they are dimers, whereas those with R = Me are monomers.166... [Pg.1177]

There is a sharp discontinuity between the extent of frequency lowering on lighter metal atom centres and those commonly observed for thorium and beyond where the P—O wavenumber is lowered by more than 100 cm-1. The most spectacular reduction is seen for complexes [UX5L]... [Pg.500]

Bleijenberg, K. C. Luminescence Properties of Uranate Centres in Solids. Vol, 42, pp. 97-128. Boeyens, J. C. A. Molecular Mechanics and the Structure Hypothesis. Vol. 63, pp. 65-101. Bonnelle, C. Band and Localized States in Metallic Thorium, Uranium and Plutonium, and in... [Pg.135]

At first, most irradiations took place in NRXs self-serve positions or its central thimble. But operators soon learned that the heavy-water moderator controlled the reactor so well that they did not need to use all the special metal rods, known as control rods, which absorbed excess neutrons. They switched three of the four control rods, all of which were located in high flux positions in the centre of the reactor, to isotope production. Surrounding the calandria of NRX was a set of vertical rods Q-rods — a code name that disguised their function) intended to hold thorium oxide for irradiation into fissile uranium-233. Experimentation soon revealed that the J-rods offered... [Pg.45]


See other pages where Thorium metal centres is mentioned: [Pg.221]    [Pg.83]    [Pg.111]    [Pg.269]    [Pg.1159]    [Pg.66]    [Pg.555]    [Pg.537]    [Pg.2998]    [Pg.206]   
See also in sourсe #XX -- [ Pg.481 ]




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Thorium metal

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