From one- to two- and three-dimensional MAS NMR solid-state experiments involving (31)P and (27)Al, we show that the structure of microporous alumino-phosphate AlPO(4)-40 contains at least four times more sites than expected, and we attribute two types of Al(IV) sites. The newly described (27)Al-(31)P MQ-HMQC opens new possibilities of describing details of three-dimensional bounded networks.

Much is known about the photoluminescence of lanthanide-containing systems, particularly amorphous silicates or organic-inorganic hybrids and crystalline metal-organic frameworks. Comparatively, stoichiometric microporous Ln-silicates are poorly studied. Here, we report the exceptional photoluminescence of microporous AV-24, K(7)[Ln(3)Si(12)O(32)] x xH(2)O (Ln(3+) = Sm(3+), Eu(3+), Gd(3+), Tb(3+)), the first silicate possessing Ln(3+)-O-Ln(3+) dimers (inter-Ln distance ca. 3.9 A), i.e., two edge-sharing {LnO(6)} octahedra embedded in a crystalline matrix. It is totally unprecedented that in AV-24 Eu(3+)-O-Eu(3+) dimers behave like discrete entities, i.e., molecules: they (i) have a unique emission signature, with pseudopoint group symmetry (C(i)), different from the symmetry (C(1)) of each individual constituent Eu(3+) ion, and (ii) exhibit the unusually long (5)D(0) lifetime of 10.29 ms (12 K). In accord with the experimental evidence, a molecular orbital model shows that the Eu(3+)-O-Eu(3+) dimers are energetically more stable than the individual metal ions.

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The azomethine ylide generated from the reaction of a corrole-3-carbaldehyde and N-methylglycine was trapped with dimethyl fumarate, dimethyl acetylenedicarboxylate and fullerene C 60 in 1,3-dipolar cycloadditions. A similar azomethine ylide generated from a corrole-2-carbaldehyde was trapped with 1,4-naphthoquinone, yielding the expected dehydrogenated 1,3-dipolar cycloadduct and a quinone-fused corrole derivative. A detailed synchrotron single-crystal X-ray diffraction analysis of the gallium(III)(pyridine) complex of 5,10,15-tris(pentafluorophenyl)corrole-3-carbaldehyde is also presented.

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