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141.
Boragermene 3 featuring a double bond between the Ge and dicoordinate B atoms has been synthesized for the first time by reacting the cyclic (alkyl)(boryl)germylene–PMe3 adduct 1 with Cl2BN(SiMe3)2 followed by reductive dehalogenation with KC8. Addition of a Lewis base (MeNHC) to 3 leads to the formation of the corresponding adduct 4 , which shows double bond character between the Ge and tricoordinate B atoms. Compound 3 undergoes hydrogenation with H2 concomitant with a complete scission of the Ge=B bond. 相似文献
142.
Naoto Sato Taiki Hayashi Kazuma Tochigi Prof. Hiroaki Wada Prof. Atsushi Shimojima Prof. Kazuyuki Kuroda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(33):7860-7865
Eight corners of a double-four ring cage-type germanoxane, containing a fluoride ion, were successfully silylated by the combination of chlorosilanes and silazanes. Three different silyl groups, trimethylsilyl, dimethylsilyl, and dimethylvinylsilyl, were attached on the corners of germanoxane cage. The solubility and reactivity of the cage modified with dimethylvinylsilyl groups were significantly increased, allowing for further reaction. Hydrosilylation reaction between dimethylvinylsilylated cage geramanoxanes and dimethylsilylated cage siloxanes afforded porous solids. Functionalization of the corners of germanoxanes with silyl groups should provide valuable building blocks in various functional materials. 相似文献
143.
Ge epitaxial layers with reasonable quality were grown on Si (1 1 1) substrates by cluster beam deposition (CBD) process. Molecular dynamics study of the low energy Ge clusters deposition process utilizing the Stillinger–Weber two- and three-body interaction potentials was carried out to compare the experimental results. Both experimental and simulation results prove that the substrate temperature plays a dominant role in the epitaxial growth of Ge films in CBD process. The influence mechanisms of temperature are discussed. 相似文献
144.
Liang Gao Zhiwei Yao Haifeng Gao Yue Sun Feixue liang 《Phosphorus, sulfur, and silicon and the related elements》2018,193(5):267-272
It was the first time that phenolic resin (PR) was used as a carbon source for the synthesis of nanostructured monometallic Mo and bimetallic CoMo carbides via carbothermal reduction route. The results showed that phase-pure β-Mo2C can be formed under an Ar atmosphere at 900°C or a H2 atmosphere above 700°C. However, almost pure CoMo carbides (Co3Mo3C and Co6Mo6C) can be obtained only under a H2 atmosphere at a low temperature of 630°C for 24 and 48 h, respectively. The role of PR in the preparation process has been investigated and a detailed formation mechanism was proposed based on the experimental results. 相似文献
145.
M. Sc. Patrik Tholen M. Sc. Zhaowen Dong Dr. Marc Schmidtmann Dr. Lena Albers Prof. Dr. Thomas Müller 《Angewandte Chemie (International ed. in English)》2018,57(40):13319-13324
The synthesis of two η5‐aminoborole complexes of germanium(II) from the reaction of a germole dianion with aminoboron dichlorides is reported. This reaction constitutes a remarkable example of a germole‐to‐borole transformation. The two aminoborole complexes of germanium(II) were fully characterized by multinuclear NMR spectroscopy, IR spectroscopy, HRMS, and, in one case, by X‐ray crystallography. The results of quantum‐mechanical calculations favor the electronic structure of a half‐sandwich complex of GeII over an ionic representation with a germanium dication stabilized by an aromatic aminoborole dianion. 相似文献
146.
AbstractThe presented method of surface modification of single-crystal silicon by chemical etching makes it possible to obtain homogeneous nanostructured silicon layers with a thickness from 3 to 60?nm for application in micro- and nano-electronics as new multifunctional material. These results could be applied to the creation of sensitive photodetectors for visible and ultraviolet ranges. The method of scanning tunneling spectroscopy shows, that the changes in the thickness of nanostructured silicon layers affect the type of conductivity, and it opens new prospective for a practical application of nanostructured silicon in nano-electronics. The obtained current-voltage characteristics of nanostructured silicon layers showed different degrees of filling of the valence band, the conduction band and the appearance on the curve of the tunneling conductance of new peaks in the gas environment. The latter gives the possibility to use the method of scanning tunneling spectroscopy for a generation of gas and biosensors. The immune biosensor is proposed in the lab on a chip form based on the nanostructured silicon for the simultaneous analysis of numerous samples. The developed biosensor based on nanostructured silicon is very promising for use in so-called systems of lab-on-chip because it can be used for rapid analysis of various immune responses and is fully compatible with silicon planar technology used in the manufacturing of the semiconductor devices. 相似文献
147.
Tsuyoshi Matsumoto Dr. Yosuke Matsui Mikinao Ito Kazuyuki Tatsumi Prof. Dr. 《化学:亚洲杂志》2008,3(3):607-613
The sulfurization of DmpGeH3 (Dmp=2,6‐dimesitylphenyl) afforded the trinuclear germanium sulfide [DmpGe(μ‐S)]2(μ‐S)2Ge(SH)‐Dmp and a series of polythiadigermabicyclo[x.1.1]alkanes (x=3, 4, 5). The reduction of the S? S bonds of these germabicycloalkanes by NaBH4 at 0 °C afforded the dinuclear mercaptogermane syn‐[DmpGe(SH)(μ‐S)2Ge(SH)‐Dmp] ( 5 ) in good yield. The reaction of [Pd(dppe)Cl2] (dppe=1,2‐bis(diphenylphosphanyl)ethane) and the dilithium salt of 5 prepared in situ by the addition of nBuLi (2 equiv) gave the Ge2PdS4 cluster [DmpGe(μ‐S)]2[(μ‐S)2Pd(dppe)], in which the dithiadigermetanedithiolate is bound to the Pd atom at the two thiolato sulfur atoms. The same reaction with [Pd(PPh3)2Cl2] gave another Ge2PdS4 cluster, [DmpGe(μ‐S)]2[(μ‐S)2Pd(PPh3)], but with the dithiadigermetanedithiolate and the Pd center conjoined through a μ‐S atom between the two germanium atoms in addition to the two thiolato sulfur atoms to form a highly distorted cluster core. The formation of two different types of Ge2PdS4 clusters represents the usefulness of 5 in the synthesis of various polynuclear complexes composed of germanium and transition metals. 相似文献
148.
149.
WU Ke-Jun ;WANG Ming-Sheng ;ZOU Jian-Ping ;XU Gang ;DING Tong-Yong ;GUO Guo-Cong ;HUANG Jin-Shun 《结构化学》2008,27(4):461-466
Mercury telluride (HgTe) nanoplatelets were obtained via a facile solvothermal reaction of mercury(I) chloride and tellurium powder in ethylenediamine (en). Mercury(I) was first applied as the mercury sources to prepare nanocrystal HgTe; moreover, the proposed mechanism for the fabrication of the sample was discussed in detail. The HgTe nanoplatelets were characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and Fourier transform infrared spectroscopy (FT-IR). The absence of IR absorption may render the title nanocrystal useful as an IR transparent material in the region. 相似文献
150.
Daniel P. Sweat 《Journal of organometallic chemistry》2008,693(14):2463-2464
A modified synthesis of tellurophene by reaction of diacetylene with sodium telluride is described. The primary modification involves the convenient in situ generation of sodium telluride by reduction of tellurium metal with NaBH4 in water. 相似文献