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81.
Tohru Ogawa 《Zeitschrift für Physik B Condensed Matter》1977,28(2):73-85
Although the five-fold symmetry conflicts with the crystalline long range order, it can appear in some finite systems. In order to search for such possibility in the microclusters in the small size limit and to clarify the roles of the electrons in the morphology, the electronic states are studied in the tight binding scheme. The single electron spectra coming from thes- andp-atomic orbitals are derived for three types of the 13-atom clusters; with the fcc-like configuration, the hcp-like and the icosahedral. If the transfer integral between two surface atoms is put equal to that between the central and a surface atom in the icosahedral case, this configuration has the lowest total electronic energy in many cases studied, but not always. The fact that a surface atom has larger number of neighbours in the icosahedral configuration is surely of great advantage. It, however, is not almighty in the quantum case.On leave from Department of Physics, Faculty of Science, Kyoto University, Kyoto 606, Japan. A part of this work was done there 相似文献
82.
Takahiro Egawa Kazuhisa Hirabayashi Dr. Yuichiro Koide Chiaki Kobayashi Dr. Naoya Takahashi Dr. Tomoko Mineno Dr. Takuya Terai Dr. Tasuku Ueno Dr. Toru Komatsu Dr. Yuji Ikegaya Prof. Norio Matsuki Prof. Tetsuo Nagano Dr. Kenjiro Hanaoka 《Angewandte Chemie (International ed. in English)》2013,52(14):3874-3877
83.
Sesquifulvalene (1) is a substance of considerable theoretical interest1 which is expected to have a significant contribution to its structure from the dipolar resonance form 1b,2 and hence an exceptionally low bond order for the central double bond. Although a wide variety of annelated and otherwise substituted sesquifulvalenes have been prepared and characterized,3 the parent substance has proved remarkably elusive. Very recently, a preparation of 1 in crystalline form has been reported, based upon elimination of an acetoxy-11,12-dihydrosesquifulvalene derivative.4 相似文献
84.
A new bis(terpyridine) derivative with a phenylacetylene framework was synthesized via a stepwise terpyridine construction strategy. The addition of ZnCl2 to a solution of the bis(terpyridine) in chloroform resulted in UV/vis and 1H NMR spectral changes because of complex formation. 相似文献
85.
Diketopyrrolopyrrole (DPP) derivatives bearing 2-pyridyl groups were synthesized, which could serve as anionic N,N′-chelate ligands consisting of two nitrogen atoms of the lactam moieties and the pyridyl groups. Coordination of the DPP ligand to boron and platinum yielded the corresponding DPP complexes. Their crystal structures exhibited coplanar structures between the DPP core and the 2-pyridyl groups, which indicated extended π-conjugation. The maximum absorption wavelength of the DPP complexes was longer than that of the corresponding DPP ligands. The choice of the introduced element affects the optical properties of the DPP complexes; the platinum complex has a longer absorption wavelength than the boron complex. The theoretical calculation revealed that these absorptions can be attributed to the π–π* transition. The introduction of the coordinating elements predominantly lowers the band gap. In addition, the substituent on the 2-pyridyl group can also modulate the energy levels. 相似文献
86.
87.
Claudia Valverde Larissa Alexandrova Esbaide Adem Takeshi Ogawa D. V. G. L. N. Rao 《先进技术聚合物》1996,7(1):27-30
Some new octa-3,5-diynylene diurethanes were prepared using 3-butyn-1-ol, and all were found to be highly light-sensitive and to undergo topochemical polymerization on exposure to irradiation. The di-n-octyldiurethane was mixed with vinyl polymers such as poly(vinyl acetate) and poly(N,N-dimethylamino-ethyl methacrylate) and the mixtures were made into thin films by spin coating. The films were then irradiated by an electron beam to polymerize the diacetylene. The purple films thus obtained showed third-order nonlinear susceptibility, χ(3), of the order of 10−10–10−11 e.s.u. 相似文献
88.
Masahito Sekiguchi Hiromichi Tanaka Noriaki Takami Akiya Ogawa Ilhyong Ryu Noboru Sonoda 《Heteroatom Chemistry》1991,2(3):427-430
The reduction of elemental selenium by samarium diiodide led to selective formation of selenolate anion species (Se2− and Se22−), the alkylation of which provided dialkyl selenides and diselenides, respectively, in excellent yields. 相似文献
89.
Satoshi Ogawa Yutaka Masutomi Naomichi Furukawa Tomoki Erata 《Heteroatom Chemistry》1992,3(4):423-429
Diaryl tellurides undergo rapid ligand exchange and disproportionation reactions on treatment with phenyllithium at −78°C. Triarylteliuranes [10-Te-3(C3)]− Li+ were identified as discrete intermediates during the reactions by 125Te, 1H, 13C, and CH-COSY NMR studies. 相似文献
90.