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31.
Shigendo Enomoto Ken-ichi Kumagai Taro Tamura Miki Hasegawa Kyoko Nakada Toshihiko Hoshi Michio Kobayashi 《Monatshefte für Chemie / Chemical Monthly》2004,29(1):471-481
Fluoranthene (FA) forms a 1:1 van der Waals complex with benzene in cyclohexane. The 1H NMR spectrum of this complex shows that the FA moiety in the complex state has five kinds of hydrogen atoms and that the 1H NMR peaks assigned to the protons attached to the naphthalene skeleton are largely shifted to higher magnetic field on complex formation with benzene. These observations indicate that the complex takes the structure of CS symmetry, in which the benzene molecule mainly interacts with the electronic system localized on the naphthalene moiety of FA. The present ab initio calculations reproduce well the 1H NMR spectral shifts mentioned above and the experimentally predicted CS structure of the complex. According to the PPP calculations for the electronic absorption spectral changes on the complex formation, the FA-benzene complex is considered to take a sandwich type structure. 相似文献
32.
Extending the results in [1], we determine the shape of the curve in S 2 which minimize the total absolute curvature in the set of nonclosed curves with fixed endpoints, end-directions and length. We deal with a more general class of curves than in [1]. 相似文献
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35.
Katsunari Enomoto Pavle Djuricanin Ilja Gerhardt Omid Nourbakhsh Yoshiki Moriwaki Walter Hardy Takamasa Momose 《Applied physics. B, Lasers and optics》2012,109(1):149-157
We propose the use of superconducting microwave cavities for the focusing and deceleration of cold polar molecular beams. A superconducting cavity with a high quality factor produces a large ac Stark shift in polar molecules, which allow us to efficiently control molecular motion. Our discussion is based on the experimental characterization of a prototype cavity: a lead–tin-coated cylindrical copper cavity, which has a quality factor of 106 and tolerates several watts of input power. Such a microwave device provides a powerful way to control molecules not only in low-field-seeking states, but also in high-field-seeking states such as the ground rotational state. 相似文献
36.
LetK be a connected graph. A spanning subgraphF ofG is called aK-factor if every component ofF is isomorphic toK. On the existence ofK-factors we show the following theorem: LetG andK be connected graphs andp be an integer. Suppose|G| = n|K| and 1 <p < n. Also suppose every induced connected subgraph of orderp|K| has aK-factor. ThenG has aK-factor. 相似文献
37.
Iron mixed-valence complex, (n-C3H7)4N[FeIIFeIII(dto)3] (dto = C2O2S2) shows a new-type of phase transition coupled with spin and charge around 120 K, where the charge transfer between the FeII and FeIII sites occurs reversibly, and shows the ferromagnetic transition at 7 K. To investigate the magnetic structure and its dimensionality of (n-C3H7)4N[FeIIFeIII(dto)3], we have synthesized a mixed crystal system, (n-C3H7)4N[FeII1?xZnIIxFeIII(dto)3], and measured its magnetic properties. In this system, the magnetic moment is reduced with increasing of Zn ratio. Moreover, the ferromagnetic interaction changes to the antiferromagnetic one and the remnant magnetization disappears between x = 0.48 and 0.96, while the charge transfer between the FeII and FeIII sites disappears above x = 0.26. In this paper, we present the magnetic dilution effect on the charge transfer phase transition and the ferromagnetic transition by means of magnetic susceptibility measurement and 57Fe Mössbauer spectroscopy. 相似文献
38.
Noriyuki Kida Masanori Hikita Izuru Kashima Masaya Enomoto Miho Itoi Norimichi Kojima 《Polyhedron》2009,28(9-10):1694-1697
A photo-sensitive organic–inorganic hybrid system (SP)[FeIIFeIII(dto)3] (SP = spiropyran, dto = C2O2S2), has recently been developed, where the photo-isomerization of the intercalated spiropyran in solid state triggers the change of the magnetic properties, including the ferromagnetic transition temperature from 5 to 22 K. We performed 57Fe Mössbauer measurement in order to probe the microscopic states of iron ions in (SP)[FeIIFeIII(dto)3] and have investigated the photo-induced effect on them. The sample without UV-irradiation shows the charge transfer phase transition between 200 and 70 K and the higher and lower temperature phases coexist below 70 K, whereas the UV-irradiated sample does not undergo the charge transfer phase transition and the higher temperature phase is stable between 200 and 6 K. 相似文献
39.
Keigo Kobayashi Prof. Hirokazu Kobayashi Prof. Mitsuhiko Maesato Dr. Mikihiro Hayashi Tomokazu Yamamoto Dr. Satoru Yoshioka Prof. Syo Matsumura Prof. Takeharu Sugiyama Dr. Shogo Kawaguchi Prof. Yoshiki Kubota Prof. Hiroshi Nakanishi Prof. Hiroshi Kitagawa 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(23):6678-6682
We report on hexagonal close-packed (hcp) palladium (Pd)–boron (B) nanocrystals (NCs) by heavy B doping into face-centered cubic (fcc) Pd NCs. Scanning transmission electron microscopy–electron energy loss spectroscopy and synchrotron powder X-ray diffraction measurements demonstrated that the B atoms are homogeneously distributed inside the hcp Pd lattice. The large paramagnetic susceptibility of Pd is significantly suppressed in Pd–B NCs in good agreement with the reduction of density of states at Fermi energy suggested by X-ray absorption near-edge structure and theoretical calculations. 相似文献
40.
Tahara T Awatsuji Y Shimozato Y Kakue T Nishio K Ura S Kubota T Matoba O 《Optics letters》2011,36(16):3254-3256
We propose single-shot digital holography which is capable of simultaneously capturing both the information of multiple phase-shifted holograms and the distribution of the polarization. In this technique, a single image sensor records both the information required for phase-shifting interferometry and that of the polarization states of objects using an array of polarizers. The essence of the technique is the capability of imaging the distribution of the polarization of three-dimensional objects with a single-shot exposure by using the space-division multiplexing of holograms. The validity of the proposed technique was confirmed by the preliminary experiments. 相似文献