MOLCAS 7: The Next Generation

Some of the new unique features of the MOLCAS quantum chemistry package version 7 are presented in this report. In particular, the Cholesky decomposition method applied to some quantum chemical methods is described. This approach is used both in the context of a straight forward approximation of the two‐electron integrals and in the generation of so‐called auxiliary basis sets. The article describes how the method is implemented for most known wave functions models: self‐consistent field, density functional theory, 2nd order perturbation theory, complete‐active space self‐consistent field multiconfigurational reference 2nd order perturbation theory, and coupled‐cluster methods. The report further elaborates on the implementation of a restricted‐active space self‐consistent field reference function in conjunction with 2nd order perturbation theory. The average atomic natural orbital basis for relativistic calculations, covering the whole periodic table, are described and associated unique properties are demonstrated. Furthermore, the use of the arbitrary order Douglas‐Kroll‐Hess transformation for one‐component relativistic calculations and its implementation are discussed. This section especially focuses on the implementation of the so‐called picture‐change‐free atomic orbital property integrals. Moreover, the ElectroStatic Potential Fitted scheme, a version of a quantum mechanics/molecular mechanics hybrid method implemented in MOLCAS, is described and discussed. Finally, the report discusses the use of the MOLCAS package for advanced studies of photo chemical phenomena and the usefulness of the algorithms for constrained geometry optimization in MOLCAS in association with such studies. © 2009 Wiley Periodicals, Inc. J Comput Chem 2010     

Experimental investigation on thermal conductivity and viscosity of aluminum nitride nanofluid

Aluminum nitride nanoparticles (AlNs) have been found to be a good additive for enhancing the thermal conductivity of traditional heat exchange fluids.At a volume fraction of 0.1,the thermal conductivity enhancement ratios are 38.71% and 40.2%,respectively,for ethylene glycol and propylene glycol as the base fluids.Temperature does not have much influence on the enhanced thermal conductivity ratios of the nanofluids,though a volume fraction of 5.0% appears to signify a critical concentration for rheology:fo...     

Refraktometrie

Ohne Zusammenfassung     

Modification of Surface Properties of Colloidal Suspensions of NixOy-SiO2 Mixed Oxides with Different Ni Contents by the Adsorption Layers of Poly(Vinyl Alcohol)

Journal of Cluster Science - The adsorption and electrokinetic properties of hybrid silica materials composed of nickel and silicon oxides (NixOy-SiO2), characterized by different contents of...     

Effect of hypercrosslinking conditions on pore size distribution and efficiency of monolithic stationary phases

Three dihalogenic solvents differing in the length of alkyl chain (1,2‐dichloroethane, 1,4‐dichlorobutane, and 1,6‐dichlorohexane) with three Friedel–Crafts alkylation catalysts varying in reactivity (AlCl₃, FeCl₃, and SnCl₄) have been used to prepare hypercrosslinked poly(styrene‐co‐vinylbenzyl chloride‐co‐divinylbenzene) columns. Hydrodynamic characteristics as well as column efficiency and mass transfer resistance were tuned by the combination of swelling solvent and alkylation reaction catalyst in the modification mixture. The column swelled in 1,6‐dichlorohexane and hypercrosslinked in the presence of AlCl₃ provided the highest column efficiency and enabled fast isocratic separations of small molecules in a RP mode. To uncover factors controlling the efficiency of hypercrosslinked monolithic columns, we have studied pore volume distribution of prepared columns. We found that column efficiency increases with the higher pore volume of pores smaller than 2 nm.     

The existence of serial correlation and its effect on the format of a championship playoff series

The specific home/away sequencing of games has been a point of contention in the championship series of professional sports leagues. This research analyses data from the National Basketball Association (NBA) Finals in developing a logistic-regression model to predict the outcome of games that takes into consideration several factors, including home-court advantage and game-to-game momentum. It is found that negative serial correlation exists such that the team that wins one game is more likely to lose the next game of the series. This model is then used to predict the probability of each team winning each of the games within the series, and these probabilities are combined to evaluate alternative playoff formats. It is found that different formats are appropriate depending on the nature of momentum, and that the format used by the NBA may minimize travel requirements, but other formats may perform better in extending the length of the series.     

Systematic Study on the Cytotoxic Potency of Commonly Used Dimeric Metal Precursors in Human Cancer Cell Lines

The cytotoxicities of seven dimeric metal species of the general formula [M(arene)Cl₂]₂, commonly used as precursors for complex synthesis and deemed biologically inactive, are investigated in seven commonly employed human cancer cell lines. Four of these complexes featured a ruthenium(II) core, where p-cymene, toluene, benzene and indane were used as arenes. Furthermore, the osmium(II) p-cymene dimer, as well as the Cp* dimers of rhodium(III) and its heavier analogue iridium(III) were included in this work (Cp*=1,2,3,4,5-pentamethylcyclopentadienide). While the cytotoxic potencies of the ruthenium(II) and osmium(II) dimers are very low (or not even detectable at applicable concentrations), surprising activity, especially in cells from ovarian malignancies (with one or two-digit micromolar IC₅₀ values), have been found for the rhodium(III) and iridium(III) representatives. This publication is aimed at all researchers using synthetic procedures based on functionalization of these dimeric starting materials to rationalize changes in biological properties, especially cytotoxicity in cancer cells.