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The photochemistry of tetraphenylacetone (1) adsorbed on the external surface of a MFI zeolite (the sodium form of LZ-105) has been investigated in combination with computational chemistry, surface area measurements, EPR analysis, and classical adsorption isotherms. All of the methods are consistent with a supramolecular structural model in which 1 is first adsorbed strongly through intercalation of a single benzene ring into a hole on the LZ-105 external surface (site I) followed by a weaker binding to the external framework between the holes (site II) until a monolayer of 1 is formed. From both computational and surface area measurements, it is estimated that the site I holes on the external surface will be filled at ca. 0.3-0.5 wt %/wt loading of 1/LZ-105, which corresponds to 6.5 x 10(18) (ca. 10(-)(5) mol) of holes or molecules of 1 adsorbed in holes per gram of zeolite. The supramolecular composition of ca. 0.3-0.5% of 1 on LZ-105 characterizes a "break point" for the photochemistry and the EPR measurements, since it represents the value for saturation of the site I holes with 1. These conclusions are supported quantitatively by experimental isotherms of the adsorption of 1 on LZ-105. Photolysis of 1 intercalated in the site I holes causes fragmentation into two isomeric supramolecular diphenylmethyl (DPM) radicals, one (DMP)(in) which is adsorbed into the internal surface and becomes strongly persistent (half-life of many weeks) and the other (DMP)(ex) which diffuses on the external surface and rapidly dimerizes (less than a few minutes) to produce the radical-radical combination product tetraphenylethane (2). Photolysis of 1 adsorbed on the solid external surface produces two supramolecularly equivalent DPM radicals (DMP)(ex) that diffuse on the external surface and rapidly dimerize to produce 2, and do not produce persistent DPM radicals.

In this paper the results obtained by using TEMPOL, TM-TEMPAMINE+, Octanoyl-, Dodecanoyl-, and Hexadecanoyl -TEMPO as spin labels for micellar solutions of C8—SO4 Na, C12-SO4Na and C16-SO4Na are reported. The analysis of ESR lineshape, of reorientational correlation time, τ, and hyperfine coupling constant, , have been carried out to obtain details on these systems. TEMPOL, TM-TEMPAMINE+ and Octanoyl-TEMPO did not give micellar solutions at the concentrations (≃10−4M) used. The ESR spectra obtained with these probes were easily interpretable over a wide range of surfactant concentrations. On the contrary, Dodecanoyl and Hexadecanoyl -TEMPO give micellar solutions at concentration

Cu(dibenzo[b,i][1,4,8,11]tetraaza[14]annulene), Cu(dbTAA), Cu(dinaphtho- [b,il[1,4,8,11]tetraaza[14]annulene), Cu(dnTAA), Cu(diphenanthro[b,i][1,4,8,11]tetraaza [14]annulene) and Cu(dpTAA) complexes have been used for synthesizing new conductive materials. Chemical oxidation of the three compounds in acetone slurries by variable amounts of iodine yielded microcrystalline conductive powders with a wide range of stoichiometries. Thermal stability of the oxidized materials was investigated by TGA and DTGA techniques showing a relationship between solid phase stability and iodine content and, together with IR data, suggests the presence of a single phase. Raman spectra show strong scatterings attributable to I3− (107 cm−1) and (160 cm−1) I5− polyiodides, the latter occurs only in highly iodinated complexes (I/Cu ratio larger than three) and the I2 presence can be excluded. Electrical conductivity measurements of powder samples of the oxidized compounds exhibit some dependence on the iodine content in the I/Cu ratio range 0–0.9. The temperature response of the conductivity of the oxidized compounds, in the range 70–220 K, is interpretable in terms of an activated formation of carriers. ESR spectra, static magnetic susceptibility and IR data as a function of the I/Cu ratio suggest that the oxidative process involves not only the copper unpaired electron, but also electrons associated with delocalized ligand orbitals on the macrocycle. Large enhancement of the conductivity is shown by Cu(dpTAA)I0.2 (1.5 S cm−1) and the temperature dependence of conductivity shows metallic behaviour starting from 200 K.