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Charge-displacement (CD) analysis has recently proven to be a simple and powerful scheme for quantitatively analyzing the profile the charge redistribution occurring upon intermolecular interactions along a given interaction axis. However, when two molecular fragments bind through complex interactions involving multiple concurrent charge flows, ordinary CD analysis is capable of providing only an averaged picture of the related charge-flow profiles and no detailed information on each of them. In this article, we combine CD analysis with a Hirshfeld partitioning of the molecular charge redistribution for a local analysis on focused portions of the molecule, allowing for a detailed characterization of one charge flow at a time. The resulting scheme—the local charge-displacement (LCD) analysis—is tested on the intriguing case of the dimethyl sulfide–sulfur dioxide complex, characterized by concurrent charge flows relating to a sulfur–sulfur homochalcogen interaction and a pair of hydrogen bonds. The LCD scheme is then applied to the analysis of multiple hydrogen bonding in the acetic acid dimer, of base-pairing interactions in DNA, and of ambifunctional hydrogen bonding in the ammonia–pyridine complex. [ABSTRACT FROM AUTHOR]

Antimony selenide (Sb2Se3) is today one of the most promising alternative materials for p-type absorbers in thin-film photovoltaics, with an optimal band-gap and a very high absorption coefficient. However, its crystal structure is extremely anisotropic and its natural carrier density is generally very low. Sb2Se3 thin films have been deposited by two different high-energy techniques: magnetron RF-sputtering (MS) and low-temperature pulsed electron deposition (LT-PED). Their dominant crystallographic orientations have been studied as a function of deposition parameters and of the different used substrates, while complete solar cells have been subsequently made with the obtained samples to confirm the dependence of conversion efficiencies on the observed (Sb4Se6)n ribbon orientation. Cu-doped Sb2Se3 thin-films have been also preliminary prepared in order to evaluate a possible route to further improve the free charge-carrier density and the cell performance.

The progress in the development of the single buffer layered coated conductors that are prepared by the technique of thermal evaporation, is discussed. These conductors have extremely thick and crack-free layers due to the improvement in their mechanical properties.

The supersonic beam of molecular oxygen ([O.sub.2]) is employed for the in situ oxidation of the superconducting [YBa.sub.2][Cu.sub.3][O.sub.7-[delta]] (YBCO) films. These films are found to exhibit excellent structural and superconducting properties after their oxidation.

We report on the room temperature, simple and cheap preparation by mechano-synthesis of polycrystalline targets of complex sulphide semiconductors, namely CuInS2 (CIS), to be used for film deposition in physical vacuum techniques such as PLD, sputtering or LT-PED. The sulphur (S)-based targets usually require expensive high pressure equipment to compensate the high S vapour pressure; nevertheless they are indispensable for the deposition of high band-gap semiconductor materials. The comparison of CIS films grown by mechano-synthesis and by commercial targets demonstrates similar material quality, making the mechano-synthesis a viable solution in the fabrication of high band-gap, S-based targets of complex chalcogenides. [ABSTRACT FROM AUTHOR]

We carry out quasi-classical trajectory calculations for the C + CH+→ C+2 + H reaction on an ad hoc computed high-level ab initio potential energy surface. Thermal rate coefficients at the temperatures of relevance in cold interstellar clouds are derived and compared with the assumed, temperature-independent estimates publicly available in kinetic data bases KIDA and UDfA. For a temperature of 10 K the data base value overestimates by a factor of 2 the one obtained by us (thus improperly enhancing the destruction route of CH+ in astrochemical kinetic models) which is seen to double in the temperature range 5-300 K with a sharp increase in the first 50 K. The computed values are fitted via the popular Arrhenius-Kooij formula and best-fitting parameters α = 1.32 ? 10-9 cm³ s-1, β = 0.1 and γ = 2.19 K to be included in the online mentioned data bases are provided. Further investigation shows that the temperature dependence of the thermal rate coefficient better conforms to the recently proposed so-called 'deformed Arrhenius' law by Aquilanti and Mundim. [ABSTRACT FROM AUTHOR]

We carry out quasi-classical trajectory calculations for the C + CH+→ C+2 + H reaction on an ad hoc computed high-level ab initio potential energy surface. Thermal rate coefficients at the temperatures of relevance in cold interstellar clouds are derived and compared with the assumed, temperature-independent estimates publicly available in kinetic data bases KIDA and UDfA. For a temperature of 10 K the data base value overestimates by a factor of 2 the one obtained by us (thus improperly enhancing the destruction route of CH+ in astrochemical kinetic models) which is seen to double in the temperature range 5-300 K with a sharp increase in the first 50 K. The computed values are fitted via the popular Arrhenius-Kooij formula and best-fitting parameters α = 1.32 ? 10-9 cm³ s-1, β = 0.1 and γ = 2.19 K to be included in the online mentioned data bases are provided. Further investigation shows that the temperature dependence of the thermal rate coefficient better conforms to the recently proposed so-called 'deformed Arrhenius' law by Aquilanti and Mundim. [ABSTRACT FROM AUTHOR]