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151.
For the linear chain system Y2[Pt(CN)4]3·21H2O a pressure induced phase transition is observed by emission spectroscopy. At ptrans=(5±0.5) kbar and T=295 K the compound undergoes a first order phase transition, in the course of which the intra-chain Pt-Pt distance R shrinks by . An approximate value had already been found at standard pressure for a temperature induced phase transition (Ttrans=218 K). 相似文献
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Stock C Heureux N Browne WR Feringa BL 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(10):3146-3153
A general approach for the easy functionalization of bare silica and glass surfaces with a synthetic manganese catalyst is reported. Decomposition of H(2)O(2) by this dinuclear metallic center into H(2)O and O(2) induced autonomous movement of silica microparticles and glass micro-sized fibers. Although several mechanisms have been proposed to rationalise movement of particles driven by H(2)O(2) decomposition to O(2) and water (recoil from O(2) bubbles, ([36,45]) interfacial tension gradient([37-42]), it is apparent in the present system that ballistic movement is due to the growth of O(2) bubbles. 相似文献
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A new copper(II) phosphonatobenzenesulfonate incorporating 4,4′‐bipyridine (4,4′‐bipy) as auxiliary ligand has been discovered through systematic high‐throughput (HT) screening of the system Cu(NO3)2·3H2O/H2O3PC6H4SO3H/4,4′‐bipy using different solvents. The hydrothermal synthesis of [Cu(HO3PC6H4SO3)(C10H8N2)]·H2O ( 1 ) was further optimized by screening various copper(II) salts. The crystal structure of 1 was determined by single‐crystal X‐ray diffraction and unveiled the presence of isolated sixfold coordinated Jahn–Teller‐distorted Cu2+ ions. The isolated CuN2O4 octahedra are interconnected by phosphonate and sulfonate groups to form chains along the c‐axis. The organic groups, namely phenyl rings and 4,4′‐bipy molecules cross‐link the chains into a three‐dimensional framework. Water molecules are found in the narrow voids in the structure which are held by weak hydrogen bonds. Upon dehydration, the structure of 1 undergoes a phase transition, which was confirmed by TG measurements and temperature dependent X‐ray powder diffraction. The new structure of 1‐h was refined with Rietveld methods. Detailed inspection of the structure revealed the directional switching of the Jahn–Teller distortion upon de/rehydration. Weak ferro‐/ferrimagnetic interactions were observed by magnetic investigations of 1 , which switch to antiferromagnetic below 3.5 K. Compounds 1 and 1‐h are further characterized by thermogravimetric and elemental analysis as well as IR spectroscopy. 相似文献
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Alfr Stock 《Analytical and bioanalytical chemistry》1903,42(8):525-525
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