COMMUNICATIONS materials causes the condensation of the silicate layers, giving the zeolite structures MCM-22 and ferrierite. Similar behavior can also be expected for RUB-15, since the silicate layer terminated with silanol groups should be the perfect subunit for the formation of the silica framework of the zeolite sodalite.
Experimental ProcedureRUB-15 crystallized from a reaction mixture with the following composition: SiO,:TMAOH:H,O = 1.00:0.75:55.52 The solution was filled in Teflon-lined autoclaves (60% filling factor) and kept in an oven at a temperature between 120 and 140 C for about four weeks. The reaction product was filtered, washed with distilled water. dried at 80 c. and subsequently identified by X-ray powder diffraction.
Tetrathiafulvalene and its derivatives can be chemically or electrochemically oxidized to yield stable radical cation salts which display unusual electrical properties. In order to increase the dimensionality of the system by extending the π‐conjugation and thus stabilizing the metallic state, while at the same time keeping the system small, the tetraiodo‐derivative (see Fig.) has been synthesized and characterized.
In Lösung monomer, im Kristall dimer ist das Dicarbonyl(pentaisopropylcyclopenta‐dienyl)eisen(I)‐Radikal 2, welches aus dem High‐spin‐Eisen(III)‐Komplex 1 durch Carbonylierung und Reduktion gebildet wird.
The synthesis of the free radicals 1‐(4'‐bromophenyl)‐3,5‐diphenyl‐verdazyl (Br‐TPV), 1‐(4'‐isopropyl‐phenyl)‐3,5‐diphenyl‐verdazyl (IP‐TPV), 1,3,5,6‐tetraphenyl‐verdazyl (Ph‐TPV), 6‐(1′‐naphthyl)‐1,3,5‐tri‐phenyl‐verdazyl (1N‐TPV), 6‐(2′‐naphthyl)‐1,3,5‐triphenyl‐verdazyl (2N‐TPV), 6‐(4′‐bromophenyl)‐1,3,5‐triphenyl‐verdazyl (BrPh‐TPV) and 1,3,5,6,6‐pentaphenyl‐verdazyl (PhPh‐TPV) is described. Their magnetic properties (static magnetic susceptibility, ESR) are reported for crystalline samples. They are compared with those of 1,3,5‐triphenyl‐verdazyl (TPV) which behaves as a quasi‐onedimensional antiferromagnet in the crystalline form. Exchange interaction is increased by a factor larger than 3 compared with TPV by the introduction of the additional ring in Ph‐TPV. For Ph‐TPV and PhPh‐TPV also the crystal structure was derived by X‐ray analysis. These results are discussed with special emphasis on their meaning for the tailoring of magnetic interactions in organic solids.
The new fullerite C60−PΦ4+ · (ClPΦ4)2 was investigated by EPR and static susceptibility. Charge transfer from PΦ4 to C60 was found to be incomplete. C60−PΦ4+ separates into a system of localized and delocalized spins at higher temperatures. At 40 K an Anderson-type localization occurs. The low-temperature susceptibility is shown to be a mixture of a Curie susceptibility and a contribution that resembles the behaviour of a spin singlet with an activated low-lying triplet state. The EPR linewidth below 40 K is only about 400 mG.
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