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181.
Michael Ruppel Dr. Dominik Lungerich Sabrina Sturm Dr. Rainer Lippert Dr. Frank Hampel Prof. Dr. Norbert Jux 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(15):3287-3296
Tetraaryltetrabenzoporphyrins (TATBPs) show, due to their optoelectronic properties, rising potential as dyes in various fields of physical and biomedical sciences. However, unlike in the case of porphyrins, the potential structural diversity of TATBPs has been explored only to little extent, owed mainly to synthetic hurdles. Herein, we prepared a comprehensive library of 30 TATBPs and investigated their fundamental properties. We elucidated structural properties by X-ray crystallography and found explanations for physical properties such as solubility. Fundamental electronic aspects were studied by optical spectroscopy as well as by electrochemistry and brought in context to the stability of the molecules. Finally, we were able to develop a universal synthetic protocol, utilizing a readily established isoindole synthon, which gives TATBPs in high yields, regardless of the nature of the used arylaldehyde and without meticulous chromatographic purifications steps. This work serves as point of orientation for scientists, that aim to utilize these molecules in materials, nanotechnological, and biomedical applications. 相似文献
182.
Paweł Wyżga Igor Veremchuk Matej Bobnar Primož Koželj Steffen Klenner Rainer Pöttgen Andreas Leithe-Jasper Roman Gumeniuk 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(23):5245-5256
The homogeneity range of ternary iron indium thiospinel at 873 K was investigated. A detailed study was focused on two distinct series (y=z): 1) a previously reported charge-balanced (In0.67+0.33y□0.33−0.33y)tetr[In2−zFez]octS4 (A1-series; □ stands for vacancy; the abbreviations “tetr” and “oct” indicate atoms occupying tetrahedral 8a and octahedral 16d sites, respectively) and 2) a new charge-unbalanced (In0.67+y□0.33−y)tetr[In2−zFez]octS4 (A2-series). Fe atoms were confirmed to exclusively occupy an octahedral position in both series. An unusual reduction of the unit cell parameter with increasing Fe content is explained by differences in the ionic radii between Fe and In, as well as by an additional electrostatic attraction originating from charge imbalance (latter only in A2-series). The studied compound is an n-type semiconductor, and its charge carrier concentration increases or decreases for larger Fe content within the A1- and A2-series, respectively. The thermal conductivity κtot is significantly reduced upon increasing vacancy concentration, whereas the change of power factor is insufficient to drastically improve the thermoelectric figure of merit. 相似文献
183.
William P. Clark Andreas Khn Rainer Niewa 《Angewandte Chemie (International ed. in English)》2020,59(1):339-342
The first quasi‐binary acetonitriletriide Sr3[C2N]2 has been synthesised and characterised. The nearly colourless crystals were obtained from the reaction of Sr metal, graphite, and elemental N2, generated by decomposition of Sr(N3)2, in a sealed Ni ampoule with the aid of an alkali metal flux. The structure of this compound was analysed via single‐crystal X‐ray diffraction and the identity of the [C2N]3? anion was confirmed by Raman spectroscopy and further investigated by quantum‐chemical methods. Computed interatomic distances within the [C2N]3? anion strikingly match the obtained experimental data. 相似文献
184.
Bridged 2,3-naphthalocyaninatoruthenium oligomers {[MacRu(L)] n } were synthesized and characterized using solid-state methods. For comparison, soluble t-butyl substituted phthalocyaninatoruthenium oligomers were prepared and their chain length examined by 1H NMR spectroscopy. The powder conductivities of all bridged compounds ([MacRu(L)] n ) were measured and the dependence of the conductivities on the bridging ligands is discussed. 相似文献
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Rainer Haag 《Nachrichten aus der Chemie》1995,43(12):1300-1301
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The incorporation of oxygen traces in chemical vapour deposited semiconductor silicon has been calculated for the temperature range of 1200–1500 K in dependence on the excess of hydrogen in the reaction gas. The results obtained correspond to the experimental data. With increasing temperatures of deposition and increasing excess of hydrogen the incorporation of oxygen decreases at a constant concentration of oxygen in the initial state. 相似文献