Publications by authors named "Patrik Pollak"

Orthoscuticellines A and B are newly isolated natural -carboline alkaloids from the moss animal . Herein, we report the first targeted total synthesis of orthoscuticelline B and an analogous synthetic method for the preparation of dihydro derivate of orthoscuticelline A. The new synthetic approach is based on commercially available and inexpensive reagents leading to a practical synthesis of the target molecules.

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Segmented contracted basis sets of quadruple-ζ quality for exact two-component (X2C) calculations are presented for the elements H-Rn. These sets are the all-electron relativistic counterparts of the Karlsruhe "def2" and "dhf" systems of bases, which were designed for Hartree-Fock and density functional treatments and-with a somewhat extended set-also for correlated treatments. The bases were optimized with analytical basis set gradients and the finite nucleus model based on a Gaussian charge distribution at the scalar-relativistic X2C level.

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Segmented contracted Gaussian basis sets optimized at the one-electron exact two-component (X2C) level - including a finite size model for the nucleus - are presented for elements up to Rn. These basis sets are counterparts for relativistic all-electron calculations to the Karlsruhe "def2" basis sets for nonrelativistic (H-Kr) or effective core potential based (Rb-Rn) treatments. For maximum consistency, the bases presented here were obtained from the latter by modification and reoptimization.

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A systematic exploration of the energy hypersurfaces of three to 13-atomic neutral and cationic binary lead-bismuth clusters is presented. Global minima for all 99 compositions (N = 3-13, n = 0-N) were obtained by a density functional theory based genetic algorithm, which was applied to every single composition, both for the neutral clusters and for the cations. Within the genetic algorithm, the energetically most favorable assignment of atom types to atom positions was found via aimed swapping of element types, based on first-order perturbation theory in the nuclear charge.

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Reactions of the binary, pseudo-homoatomic Zintl anion (Pb2 Bi2 )(2-) with Ln(C5 Me4 H)3 (Ln=La, Ce, Nd, Gd, Sm, Tb) in the presence of [2.2.2]crypt in ethane-1,2-diamine/toluene yielded ten [K([2.

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For lanthanides, segmented contracted Gaussian basis sets of double-ζ valence to quadruple-ζ valence quality are presented, with two different polarization sets for each level of quality. The bases are designed for use in connection with small-core Wood-Boring effective core potentials. A set of compounds representing most lanthanides in their common oxidation states is used to assess the quality.

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