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991.
992.
Christoph E. Strasser William F. Gabrielli Oliver Schuster Stefan D. Nogai Stephanie Cronje Helgard G. Raubenheimer 《Journal of chemical crystallography》2009,39(7):478-483
Abstract Two crystal structures of tris(azolyl)phosphines, PR3 [R′ = 1-methylimidazol-2-yl (1) or R′′ = 4-methylthiazol-2-yl (2)], and the crystal structure of the sulfurisation product of 2, R′′3PS (3), were determined. All compounds crystallise in polar space groups, 1 in the orthorhombic space group Pna21 with cell parameters a = 13.9779(15) ?, b = 9.2492(10) ? and c = 10.2439(11) ?; 2 in the trigonal space group, R3c, with a = 15.2383(10) ? and c = 10.5882(13) ? and 3 in the orthorhombic space group, Cmc21, with a = 13.466(3) ?, b = 9.308(2) ? and c = 12.207(3) ?.
Graphical Abstract This article presents two crystal structures of tris(azolyl)phosphines and one of a tris(thiazolyl)phosphine sulfide, a compound
which show potential for wide application in coordination chemistry due to their multidentate nature.
相似文献
993.
Krzysztof Chełminski Dietmar Hömberg Oliver Rott 《Nonlinear Analysis: Real World Applications》2011,12(1):615-632
This paper deals with a new mathematical model to characterize the interaction between machine and workpiece in a milling process. The model consists of a harmonic oscillator equation for the dynamics of the cutter and a linear thermoelastic workpiece model. The coupling through the cutting force adds delay terms and further nonlinear effects. After a short derivation of the governing equations it is shown that the complete system admits a unique weak solution. A numerical solution strategy is outlined and complemented by numerical simulations of stable and unstable cutting conditions. 相似文献
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Mathematical Programming - In this article we study the problem of signal recovery for group models. More precisely for a given set of groups, each containing a small subset of indices, and for... 相似文献
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Dr. Oliver R. Maguire Dr. Albert S. Y. Wong Mathieu G. Baltussen Peer van Duppen Aleksandr A. Pogodaev Prof. Dr. Wilhelm T. S. Huck 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(7):1676-1682
Current efforts to design functional molecular systems have overlooked the importance of coupling out-of-equilibrium behaviour with changes in the environment. Here, the authors use an oscillating reaction network and demonstrate that the application of environmental forcing, in the form of periodic changes in temperature and in the inflow of the concentration of one of the network components, removes the dependency of the periodicity of this network on temperature or flow rates and enforces a stable periodicity across a wide range of conditions. Coupling a system to a dynamic environment can thus be used as a simple tool to regulate the output of a network. In addition, the authors show that coupling can also induce an increase in behavioural complexity to include quasi-periodic oscillations. 相似文献
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Ana Sánchez-Grande Dr. José I. Urgel Aleš Cahlík Dr. José Santos Shayan Edalatmanesh Eider Rodríguez-Sánchez Dr. Koen Lauwaet Dr. Pingo Mutombo Prof. Dana Nachtigallová Reed Nieman Prof. Hans Lischka Dr. Bruno de la Torre Prof. Rodolfo Miranda Dr. Oliver Gröning Prof. Nazario Martín Prof. Pavel Jelínek Prof. David Écija 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(40):17747-17752
We report on the synthesis and characterization of atomically precise one-dimensional diradical peripentacene polymers on a Au(111) surface. By means of high-resolution scanning probe microscopy complemented by theoretical simulations, we provide evidence of their magnetic properties, which arise from the presence of two unpaired spins at their termini. Additionally, we probe a transition of their magnetic properties related to the length of the polymer. Peripentacene dimers exhibit an antiferromagnetic (S=0) singlet ground state. They are characterized by singlet–triplet spin-flip inelastic excitations with an effective exchange coupling (Jeff) of 2.5 meV, whereas trimers and longer peripentacene polymers reveal a paramagnetic nature and feature Kondo fingerprints at each terminus due to the unpaired spin. Our work provides access to the precise fabrication of polymers featuring diradical character which are potentially useful in carbon-based optoelectronics and spintronics. 相似文献