Results of tight-binding calculations on metastable spin-polarized carbon clusters C 8 (prismanes) are presented. It is shown that those clusters can form ensembles due to intercluster bonding. The binding energy of a given metastable configuration decreases monotonously with the total spin S, while the activation energy for the decay of a metastable state has distinct maxima as a function of S...

The electrophilic addition of halogens is one of the most characteristic reactions of unsaturated hydrocarbons. In organic textbooks the cyclic three-membered halonium ions are postulated as key intermediates to account for the observed stereochemistry in halogenation reactions of alkenes. Strong experimental evidence supporting the mechanism comes from the reactions of hindered alkenes, which ...

An application of an ultra-short femto-second (fs) pulsed laser (30 fs, 800 nm, 1 kHz) radiation under a simultaneously varied fluence (0.6, 1.2 and 1.8 J/cm2) number pulses (2000–32,000 per irradiation site) to process diamond has been investigated determine optimal conversion the diamond's tetrahedral sp3 phase into aromatic sp2 with high degree crystallinity without formation olefinic fracti...