1994 Fiscal Year Final Research Report Summary
Generation of Supra-molecular Cluster Structure and its Binding Condition
| Project/Area Number |
04403002
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| Research Category |
Grant-in-Aid for General Scientific Research (A)
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| Allocation Type | Single-year Grants |
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| Research Field |
物理化学一般
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| Research Institution | KYUSHU UNIVERSITY |
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Principal Investigator |
NISHI Nobuyuki Kyushu University, Faculty of Science, Professor, 理学部, 教授 (60013538)
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| Co-Investigator(Kenkyū-buntansha) |
OHASHI Kazuhiko Kyushu University, Facutly of Science, Reseach Associate, 理学部, 助手 (80213825)
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| Project Period (FY) |
1992 – 1994
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| Keywords | Cluster / Supramolecule / Ethanol / Water / X-ray diffraction / Mass spectrometry / Infrared Spectroscopy |
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| Research Abstract |
The structure of clusters in ethanol-water binary solutions at x_E (ethanol mole fraction) <greater than or equal>0.2 is investigated by the mass spectrometric analysis of the clusters isolated from liquid droplets and X-ray diffraction measurements of intact solution. Average numbers of water molecules (N^a) of the ethanol m-mer hydrates (5<m<15) in the mixtures at 0.2<less than or equal>x_E<less than or equal>0.8 are found to be expressed by a function of water mole fraction (x_w) : Na^a={(m/4.2) -1} ^2 (x_w+0.85), suggesting that the fundamental structure of the ethanol polymer-hydrates is invariable in thie region. An inflection point of N^a was found at x_3<approximately equal>0.2. The radial distribution functions (RDFs) fromthe X-ray measurements demonstrated a decrease of linear hydrogen bonds at 2.8 * with increasing x_E, while keeping the strongest peak at 4.8 * in 0.4<less than or equal>x_E<less than or equal>1.0. On the basis of the composition analysis of the mass spectra and the concentration dependence of RDFs, we propose the most likely model of ethanol-water binary clusters formed in the region 0.2<less than or equal>x_E<less than or equal>0.8.
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