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Efforts to identify and develop new superconducting materials continue apace, motivated by both fundamental science and the prospects for application. For example, several new superconducting material systems have been developed in the recent past, including calcium-intercalated graphite compounds (1), boron-doped diamond (2) and-most prominently-iron arsenides such as [LaO.sub.1-x][F.sub.x]FeAs (ref. 3). In the case of organic superconductors, however, no new material system with a high superconducting transition temperature ([T.sub.c]) has been discovered in the past decade. Here we report that intercalating an alkali metal into picene, a wide-bandgap semiconducting solid hydrocarbon, produces metallic behaviour and superconductivity. Solid potassium-intercalated picene ([K.sub.x]picene) shows [T.sub.c] values of 7K and 18 K, depending on the metal content. The drop of magnetization in [K.sub.x]picene solids at the transition temperature is sharp (, The metal doping of organic molecular compounds and graphites, solids with p-electron networks, has been extensively studied in the search for novel physical properties, such as metallic behaviour and superconductivity [...]

A study of the dissociation mechanism of the S-S bond in the [alpha],[alpha']-dinaphthyl disulfide radical anion (NpSSNp.-) in organic solution on the bases of transient absorption measurements and DFT calculations is presented. It was seen that NpSSNp.- undergoes S-S bond cleavage to form NpS and Np[S.sup.-] with a first-order rate constant in the magnitude of [10.sup.6][s.sup.-1] in solution at room temperature.

Novel macrocylic and medium-size stilbenophanes tethered by silyl chains that were synthesized and their photochemical and photophysical properties that were examined are discussed. When the distance between two stilbene units in the stilbenophanes was sufficiently small, intramolecular excimer emission was observed.

An investigation of the photochemical properties of photoinduced omega-bond dissociation in p-benzoylbenzyl phenyl sulfide (BBPS) in solution is conducted by time-resolved EPR and laser flash photolysis techniques. BBPS is demonstrated to undergo photoinduced omega-bond cleavage to yield the p-benzoylbenyl radical (BBR) and phenyl thiyl radical (PTR) at room temperature.

The triplet-synthesized photoreactions of the title biplanophane system, the photoisomer of a 2,11-diaza[3,3](9,10)anthracenoparacyclophane derivative, were investigated by stationary and laser-flash photolyses using xanthone (XT) and benzophenone (BP) as triplet sensitizers. The results of the product studies and the kinetic analyses for the photochemical and photophysical processes are described.

Stepwise laser photolysis techniques were used to investigate the photochemical profiles of [BETA]-bond dissociation in highly excited triplet states ([T.sub.n]) of biphenyl derivatives having C-O bonds. The findings show reveal that the [[Phi].sub.dec] was related to the energy difference ([DELTA]E) between the bond dissociation energy (BDE) and the [E.sub.RT] and the rate ([k.sub.dis]) of [beta]-cleavage in the [T.sub.R] state was formulated as being simply proportional to [DELTA]E.

The reactivity and mechanism of omega-bond disassociation in naphthyl phenyl ketones having a phenylthiyl moiety as a leaving group, p-(alpha-napththoyl)benzyl phenyl sulfide (NBPS) and 4-benzoyl-I-naphthylmethyl phenyl sulfide (BNMPS), in solution are explored by laser flash photolysis techniques. Both ketones underwent omega-bond cleavage of the C-S bond to release the phenyl thiyl radical at room temperature.

A report that the fast C-O bond cleavage occurs to produce naphthylmethyl radicals from naphthalene substituted by 1- or2-Ch2OR, 1,4-(CH2OR)2, or 1,8-(CH2OR)2 in the Tn states is presented. The results reveal that the C-O bond cleavage and production of free radicals, such as BPCH2., C6H5O., and CH3O., are likely to be performed by a stepwise two-photon excitation.