Theoretical Study on fluctuations in condensed phases and nonlinear spectroscopies

凝聚相涨落与非线性光谱的理论研究

• 批准号: 13640506
• 负责人: SAITO Shinji
• 金额: $ 2.24万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13640506/
• 关键词: two-dimensional Raman spectroscopy; molecular dynamics simulation; Anharmonic Dynamics; Melting of ice; IR photon echo; cheunical reactions in supercritical water; 超臨界水中の化学反応; 凝縮系の揺らぎ; 高次非線形分光; 位相空間ダイナミクス; 水の結晶化; ギ酸の解離反応; 超臨界水; 2次元ラマン分光; 分子動

In this study, we have investigated fluctuations in condensed phases ; multidimensional vibrational spectroscopy, phase transition dynamics of water, and chamical reactions in supercritical water.We have been theoretically investigating two-dimensinal (2D) Raman spectroscopy of liquids. As a two-dimensional NMR method, the multidimensional vibrational spectroscopies provide detailed information on dynamics that canot be obtained in conventional Raman spectroscopies. It was found that there exist changes in sign near the second time variable t_2 in the 2D Raman signals calculated with molecular dynamics simulation. The changes in sign are not seen in the signals based on normal mode descriptions. Thus it was found that they are related to anharmonic dynamics of the system. Various analyses have been made to understand what kind of dynamics is seen in the 2D Raman signals of liquid CS_2. We have found that a rotation-rotation dynamical coupling is the dominant contribution of the 2D Raman signal of liquid CS_2. The temperature dependence of the 2D Raman signal has been analyzing.We have analyzed the melting process of ice by using molecular dynamics simulations. It was found that the melting is followed by disorders of hydrogen bond network in the ice. We have analyzed the dynamics of translational and rotational motions and density fluctuation in the melting process.The dissociation of formic acid in a sub- and super-critical water has been also investigated.

在这项研究中，我们研究了凝聚相的波动；多维振动光谱、水的相变动力学和超临界水中的化学反应。我们一直在理论上研究液体的二维 (2D) 拉曼光谱。作为一种二维核磁共振方法，多维振动光谱提供了传统拉曼光谱无法获得的详细动力学信息。发现分子动力学模拟计算得到的二维拉曼信号在第二时间变量t_2附近存在符号变化。在基于正常模式描述的信号中看不到符号的变化。因此发现它们与系统的非简谐动力学有关。为了了解液体 CS_2 的二维拉曼信号中看到的动力学类型，我们进行了各种分析。我们发现旋转-旋转动力耦合是液体 CS_2 二维拉曼信号的主要贡献。分析了二维拉曼信号的温度依赖性。我们利用分子动力学模拟分析了冰的融化过程。研究发现，冰的融化伴随着氢键网络的紊乱。我们分析了熔化过程中平移和旋转运动的动力学以及密度波动。还研究了甲酸在亚临界和超临界水中的离解。

项目成果

S.Saito and I.Ohmine: "Off-Resonant Fifth-order Response Function for Two-Dimensional Raman Spectroscopy of Liquid CS_2 and H_2O"Phys.Rev.Lett.. 88. 207401-1-207401-4 (2002)

S.Saito 和 I.Ohmine：“液体 CS_2 和 H_2O 二维拉曼光谱的非共振五阶响应函数”Phys.Rev.Lett.. 88. 207401-1-207401-4 (2002)

T.Yagasaki, S.Saito, I.Ohmine: "A Theoretical Study on Decomposition of Formic Acid in Sub-and Super-Critical Water"J. Chem. Phys.. 117・2. 7631-7639 (2002)

T.Yagasaki、S.Saito、I.Ohmine：“亚临界和超临界水中甲酸分解的理论研究”J. Chem. 117・2 (2002)

T.Yagasaki, S.Saito, I.Ohmine: "A Theoretical Study on Decomposition of Formic Acid in Sub-and Super-Critical Water"J. Chem. Phys.. 117. 7631-7639 (2002)

T.Yagasaki、S.Saito、I.Ohmine：“亚临界和超临界水中甲酸分解的理论研究”J。

L.J.Kaufman, S.Saito, L.D.Ziegler, I.Ohmine, G.R.Fleming: "Heterodyne detected fifth-order nonresonant Raman spectroscopy of CS_2 : Evidence for anharmonic coupling"Ultrafast Phenomena XIII (eds. R. D. Miller, M. Murnane, N. F. Scherer, and A. M. Weiner)

L.J.Kaufman、S.Saito、L.D.Ziegler、I.Ohmine、G.R.Fleming：“外差检测到 CS_2 的五阶非共振拉曼光谱：非谐波耦合的证据”超快现象 XIII（eds. R. D. Miller、M. Murnane、N. F. Scherer，

I.Ohmine, M.Matsumoto, S.Saito, A.Baba, Y.Yonekura, S.Ogasawara, H.Inagaki, C.Kobayashi: "Landscape of Water Dynamics and Chemical Reactions"New Kinds of Phase Transitions : Transformations in Disordered Substances (eds, V. V. Braznkin, S. V. Buldyrev, V.

I.Ohmine、M.Matsumoto、S.Saito、A.Baba、Y.Yonekura、S.Ogasawara、H.Inagaki、C.Kobayashi：“水动力学和化学反应的景观”新型相变：无序中的转变