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Parametric computations of electron energy distribution function (EEDF) and of electron mobility in photoplasma of sodium mixture with different inert gases are presented. The conditions of a weak external electric field are considered when electron heating is provided by super-elastic impacts (second kind collisions) with excited sodium atoms. It is demonstrated that nonequilibrium EEDF arising in heavy inert gases due to Ramsauer minimum on the cross section of elastic electron-atom collisions can considerably affect electron mobility. It results in complex nonmonotonous dependence of electron mobility from partial pressure of mixture components, plasma ionization degree, and from resonant-excited sodium atoms density. In Na + Kr, Na + Xe mixtures by low plasma ionization degree, the electron mobility can differ by more than two times from the one calculated with Maxwellian EEDF. In Na + Ar mixture, in certain conditions, the mobility may take on negative values. The critical plasma parameters (sodium excited atoms density, plasma ionization degree, electric field strength) determining this effect are revealed. The influence of nonequilibrium EEDF on electron mobility helps to explain abnormally low conductivity of photoplasma in Na + Ar mixture observed earlier in the experiment. Index Terms - Conductivity, distribution function, plasma properties.

Reactions of the [(tppm)Au3Cl3] [tppm = tris(diphenylphosphanyl)methane] precursor and CuI ions with a stoichiometric amount of the corresponding linear mono- [HC2(C6H4) nC6H5; n = 1, 2] and diacetylenes [HC2(C6H4) nC2H; n = 1-3] that contain extended polyaryl moieties afford a series of luminescent heterometallic complexes with a common structural motif based on the {(AuC2)3Cu} cluster core. The complexes obtained were characterized by using X-ray crystallography and NMR spectroscopy. All compounds studied display dual singlet and triplet luminescence, the former component of which can be completely suppressed in concentrated solution by a self-absorption phenomenon. The results of the photophysical measurements together with the quantum chemical calculations (PBE0-DFT level of theory) indicate that singlet emission originates mainly from copper-perturbed intraligand transitions, whereas the phosphorescence can be assigned to the {(AuC2)3Cu} core-centered transitions. Due to the low contribution of the gold atoms to the orbitals responsible for the singlet and triplet emission, the emissive excited states are very weakly coupled, thereby resulting in a negligible energy transfer between these excited states. [ABSTRACT FROM AUTHOR]

[Display omitted] Using ultrafast transient absorption spectroscopy, primary photophysical processes in aqueous and acetonitrile solutions of the trans , trans , trans -[Ptiv (N 3) 2 (py) 2 (OH) 2 ] complex, which is interesting as a potential light-activated anticancer drug, were investigated. A mechanism for early photoprocesses has been proposed, including ultrafast intersystem crossing and reductive dissociation. [ABSTRACT FROM AUTHOR]