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991.
992.
Ingmar Krabbes Wilhelm Seichter Karsten Gloe 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):e178-e178
The title compound, [Ni{N(CH2CH2OH)3}2](CH3COO)2, was prepared and the structure determined. It is isostructural with the copper(II) analogue. 相似文献
993.
994.
Thomas Lainer Dr. Deepak Dange Michael Pillinger Prof. Dr. Roland C. Fischer Prof. Dr. Anne-Marie Kelterer Prof. Dr. Cameron Jones Dr. Michael Haas 《ChemistryOpen》2022,11(3):e202100240
A convenient metal-free approach towards an N-heterocyclic carbene (NHC)-coordinated disilene 2 is described. Compound 2 , featuring the disilene incorporated in cyclopolysilane framework, was obtained in good yield and characterized using NMR spectroscopy and X-ray crystallography. Density functional theory (DFT) calculations of the reaction mechanism provide a rationale for the observed reactivity and give detailed information on the bonding situation of the base-stabilized disilene. Compound 2 undergoes thermal or light- induced (λ=456 nm) NHC loss, and a dimerization process to give a corresponding dimer with a Si10 skeleton. In order to shed light on the dimerization mechanism, DFT calculations were performed. Moreover, the reactivity of 2 was examined with selected examples of transition metal carbonyl compounds. 相似文献
995.
Sara Fateixa Manon Wilhelm Helena I. S. Nogueira Tito Trindade 《Journal of Raman spectroscopy : JRS》2016,47(10):1239-1246
Textile fibres containing Ag nanoparticles have been widely explored for a number of antimicrobial fabrics. Moreover, it is well‐known that textile dyeing is a critical stage in the manufacture thereof. This research shows that surface enhanced Raman scattering (SERS) and Raman imaging can be used with advantage in the monitoring of this process. Using Ag containing linen fibres stained with methylene blue (MB), it was possible to map the local distribution of the MB dye in the fibres by Raman imaging. MB was selected as the SERS molecular probe and as a model dye. Composites of linen fibres and Ag nanoparticles were prepared by distinct methods and used as SERS substrates in order to evaluate the effect of the preparative method on the Raman images. Our results demonstrate that by using Raman imaging associated to the presence of Ag nanoparticles, it is possible to distinguish the local distribution of the dye on the textile surface. This investigation allows to foreseeing the use of this technique in terms of quality control of Ag containing fabrics, which is a market in great expansion. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
996.
997.
Shen J Chagarov EA Feldwinn DL Melitz W Santagata NM Kummel AC Droopad R Passlack M 《The Journal of chemical physics》2010,133(16):164704
Interfacial bonding geometry and electronic structures of In(2)O on InAs and In(0.53)Ga(0.47)As(001)-(4×2) have been investigated by scanning tunneling microscopy/scanning tunneling spectroscopy (STM/STS). STM images show that the In(2)O forms an ordered monolayer on both InAs and InGaAs surfaces. In(2)O deposition on the InAs(001)-(4×2) surface does not displace any surface atoms during both room temperature deposition and postdeposition annealing. Oxygen atoms from In(2)O molecules bond with trough In/Ga atoms on the surface to form a new layer of O-In/Ga bonds, which restore many of the strained trough In/Ga atoms into more bulklike tetrahedral sp(3) bonding environments. STS reveals that for both p-type and n-type clean In(0.53)Ga(0.47)As(001)-(4×2) surfaces, the Fermi level resides near the valence band maximum (VBM); however, after In(2)O deposition and postdeposition annealings, the Fermi level position is close to the VBM for p-type samples and close to the conduction band minimum for n-type samples. This result indicates that In(2)O bonding eliminates surface states within the bandgap and forms an unpinned interface when bonding with In(0.53)Ga(0.47)As/InP(001)-(4×2). Density function theory is used to confirm the experimental finding. 相似文献
998.
V. Ney S. Ye T. Kammermeier K. Ollefs A. Ney T.C. Kaspar S.A. Chambers F. Wilhelm A. Rogalev 《Journal of magnetism and magnetic materials》2010,322(9-12):1232-1234
We compare the magnetic properties of two types of Co-doped ZnO films grown on sapphire with distinct structural quality. SQUID magnetometry as well as element-specific synchrotron studies reveal pure paramagnetic behavior for the samples with the highest structural quality, whereas samples with reduced structural quality exhibit superparamagnetic blocking behavior. In this sample signatures of phase separation are detected by X-ray diffraction and X-ray linear dichroism which accounts for the superparamagnetic blocking. 相似文献
999.
1000.
Giordano Poneti Matteo Mannini Dr. Lorenzo Sorace Dr. Philippe Sainctavit Dr. Marie‐Anne Arrio Dr. Andrei Rogalev Dr. Fabrice Wilhelm Dr. Andrea Dei Prof. 《Chemphyschem》2009,10(12):2090-2095
The role of the cobalt ion in the entropy‐ and optically‐driven valence tautomeric (VT) interconversion exhibited by the [Co(Me2tpa)(DTBdiox)](PF6)?C6H5CH3 complex (Me2tpa=bis (6‐methyl‐(2‐pyridylmethyl))(2‐pyridylmethyl)amine, DBdiox=3,5‐ditertbutyl‐dioxolene) is established by means of X‐ray absorption spectroscopy (XAS). Analysis of the pre‐edge features at 6 and 300 K in the Co K‐edge XAS spectra using a ligand field multiplet approach allows us to obtain detailed information on the electronic structures of the metal ion in the two redox isomers. The temperature dependence of the spectra confirms the occurrence of a thermally induced VT transition and suggests that nucleation and distortion of the phase boundaries take place during the process. Moreover, optically induced metastable state formation is monitored at low temperatures—with a high degree of reproducibility—without changing the position of measurement on the sample during the experiment. This result paves the way for the use of such a highly sensitive technique for the investigation of photoswitchable materials in non‐crystalline and nanostructured environments. 相似文献