Schrödinger

About: Schrödinger is a based out in . It is known for research contribution in the topics: Sputtering & Ion. The organization has 1621 authors who have published 2200 publications receiving 81554 citations.

Darstellung und Kristallstruktur von CsSb2Se4

Abstract: CsSb2Se4 wurde durch hydrothermale Reaktion von Cs2CO3 mit Sb2Se3 bei einer Temperatur von 115°C dargestellt. Eine Rontgenstrukturanalyse ergab, das die Verbindung Polyselenoantimonat(III)-Anionen (Sb2Se4-)n beinhaltet, die sowohl (Sb)SeSb- als auch (Sb)SeSe(Sb)-Brucken aufweisen. Fur eines der beiden unabhangigen Sb-Atome wird eine ψ-tetraedrische Koordination, fur das andere eine ψ-trigonalbipyramidale Koordination gefunden. Die SbSe-Polyeder sind uber gemeinsame Ecken und Kanten sowie uber direkte SeSe-Bindungen zu Schichten vernetzt. Preparation and Crystal Structure of CsSb2Se4 CsSb2Se4 was prepared by hydrothermal reaction of Cs2CO3 with Sb2Se3 at a temperature of 115°C. An X-ray structural analysis demonstrated that the compound contains polyselenoantimonate(III) anions (Sb2Se4−)n, which display both (Sb)SeSb and (Sb)SeSe(Sb) bridges. A ψ-tetrahedral coordination is observed for one of the independent Sb atoms, a ψ-trigonal bipyramidal coordination for the other. The SbSe polyhedra are linked through joint corners and edges and in addition via direct SeSe bonds into sheets.

Wismutverbindungen mit voluminösen, mehrfach alkylierten Cyclopentadienyl‐Liganden

Abstract: Bismuth Compounds with Crowded Multiply Alkylated Cyclopentadienyl Ligands1 Bismuth complexes of alkylated cyclopentadienyl ligands are obtained in good yield on treating bismuth(III) halides with tetraisopropylcyclopentadienylsodium or 1,2,4-tri-tert-butyl-cyclopentadienyllithium. A 1:1 stoichiometric ratio gives the complexes [Cp4iBiCl2] (1), [Cp3tBiCl2] (2), and [Cp4iBiI2] (3) (Cp4i = C5iPr4H, Cp3t = C5H2tBu3-1,2,4). According to X-ray crystal structure analyses, 1 and 3 display dimeric structures with two bridging and two terminal halogeno ligands and η3-coordination of the cyclopentadienyl rings. With half an equivalent of tetraisopropylcyclopentadienylsodium BiCl3 forms [Cp4iBi2Cl5] (4). An X-ray crystal structure analysis of 3 reveals a central Bi2Cl10 core of two edge-sharing BiCl6 octahedra coordinated to two Bi(η5-Cp4i) fragments generating a framework of two face-sharing cubes. Reaction of two equivalents of 1,2,4-tri-tert-butylcyclopentadienyllithium with BiCl3 yields deep purple [Cp3t2BiCl] (5), a bent sandwich complex with an η3,η2-bonding mode of the cyclopentadienyl ligands. Attempted formation of the octaisopropyl analogue of 5 from BiCl3 and two equivalents of tetraisopropylcyclo-pentadienylsodium with elimination of propene gives [Cp4iCp3iBiCl] (6) (Cp3i = C5H2iPr3). Use of monodeuterated tetraisopropylcyclopentadienylsodium in the second substitution step gave pure [Cp4i([D1]Cp3i)BiCl] ([D1]6) proving the absence of ring exchange reactions under the reaction conditions employed and elimination of propene from the second incoming sterically crowded tetraisopropylcyclopentadienyl ring system. The importance of proper choice of solvent and reaction conditions on the formation of alkylated cyclopentadienyl bismuth derivatives is demonstrated by extensive formation of 1,1′,3,3′,5,5′-hexa-tert-butyldihydrofulvalene (7) from 1,2,4-tri-tert-butylcyclopentadienylsodium and BiCl3.

Laser-powered tape placement process – simulation and optimization

Abstract: The laser-assisted thermoplastic tape placement process for unidirectional carbon fiber reinforced polyetheretherketon (CF PEEK) tapes was investigated. In this process, tapes are melted, laid-up on a tool, and consolidated under a roller. As an out of autoclave process, thermoplastic tape placement has high potential for aerospace manufacturing industry. To optimize laser settings for high efficiency and reproducibility, a thermal simulation was created. Process windows are calculated based on critical process temperatures. A parameter study was conducted to investigate the influence of lay-up speed and laser settings, especially laser beam height and angle of impact, on the process. For different lay-up speeds, optimum values and limits of laser settings are found to gain autoclave quality with high material output and high reproducibility. Peel specimens have been produced to verify simulated optimum parameters, which showed good agreement. Economical potential of thermoplastic tape placement was shown...