Spatial and temporal scale of cooperative motions in supercooled liquids

过冷液体中协同运动的空间和时间尺度

• 批准号: 09440199
• 负责人: NOMURA Hiroyasu
• 金额: $ 7.04万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09440199/
• 关键词: supercooled liqids; cooperative motiom; ultrasonic spectroscopy; dielectric spectroscpy; Raman spectroscopy; Boson Peak; highly viscous liquids; disaccharide; ボゾンピーク; 二糖類水溶液

The Spatial and temporal scale for cooperative motions in supercooled liquids were investigated using ultrasonic spectroscopy, dielectric spectroscopy and Raman spectroscopy technique in the wide temperature range. The results are listed as follows.(1) The ultrasonic spectra in the frequency range from 5 MHz to 10 GHz for propylene glycol (PG) , 1, 2, 6-hexanetriol and tetra (ethylene glycol) (PEG) -hexanetriol binary mixtures have been measured as a function of temperature. For PG, hexanetriol and PEG-hexanetriol binary mixtures, the velocity dispersions attributed to the structural relaxation are observed and smooth master curves are obtained in the measured frequency and temperature ranges. Averaged relaxation times of the structural relaxation processes are in reasonable agreements with those estimated by the linear viscoelastic theory.(2) Complex dielectric spectra of PEG were measured in the microwave region in the temperature range from 248 to 298 K.The reduced complex permittiv … More ity could be superimposed on a master curve. The observed point of inflection in the high frequency side at the Cole-Cole plot of reduced permittvity suggest that there are fast cooperative process in the picosecond region.(3) A broad peak known as a boson peak is observed in the low-frequency spectra in PEG, hexanetriol and PEG-hexanetriol binany mixture with composition ratio of 1 : 1. The extended disorder-induced scattering model reproduces the line shape of the boson peak and structural correlation length is estimated. The structural correlation length are order of 1 nm and the fluctuation of times of are around 10 ps.(4) Raman spectra of PEG from 750 to 950 cm^<-1> indicate that the conformation in the liquid state depends on temperature and may approach to that in the crystalline state with decreasing temperature down to the glass transition temperature 7_g.(5) Complex dielectric spectra of concentrated aqueous solution of the disaccharide, trehalose and maltose, were measured in the microwave region. The relaxation time of trehalose is larger than that of maltose similar to the case of ultrasonic relaxation. The activation energies for both solution is smaller than that of water. Less

利用超声光谱、介电光谱和拉曼光谱技术研究了宽温度范围内过冷液体协同运动的空间和时间尺度。(1)测量了丙二醇(PG)、1，2，6-己三醇和四(乙二醇)-己三醇二元混合物在5~10 GHz频率范围内的超声频谱随温度的变化关系。对于PG、正己三醇和聚乙二醇-正三醇二元混合物，观察到了结构松弛引起的速度色散，并在测量的频率和温度范围内获得了平滑的主曲线。结构弛豫过程的平均弛豫时间与线性粘弹性理论估算的结果吻合较好。(2)在248K到298K的温度范围内，测量了聚乙二醇复介电性能。折合复介电常数…在一条主曲线上可以叠加更多的弹性。在介电常数折减的Cole-Cole图上观察到高频侧的拐点，表明在皮秒区有一个快速的合作过程。(3)在组成比为1：1的聚乙二醇、六醇和聚乙二醇-六三醇双组分混合物的低频光谱中观察到一个宽峰，称为玻色子峰。扩展的无序诱导散射模型再现了玻色子峰的线形，并估算了结构关联长度。(4)聚乙二醇750~950 cm^~(-1)~(-1)的拉曼光谱表明，其液态构象与温度有关，在玻璃化转变温度7g以下可接近结晶态构象。(5)在微波区测量了二糖、海藻糖和麦芽糖的浓水溶液的复介电谱。海藻糖的松弛时间大于麦芽糖，与超声波松弛的情况相似。两种溶液的活化能均小于水的活化能。较少

项目成果

H.Nomura, S.Koda, T.Matsuoka, T.Noudou, R.Buchner and J.Barthel: "Cooperative Motion in Liquids in the Strong Interaction Field" Journal Molecular Liquids. 78. 29-36 (1998)

H.Nomura、S.Koda、T.Matsuoka、T.Noudou、R.Buchner 和 J.Barthel：“强相互作用场中液体的协作运动”杂志分子液体。

T.Shibata et al.: "Deporlarized Light Scattering in the Isotropic Phase of Liquid Crystals" Journal Chemical Physics. 109・5. 2038-2042 (1998)

T. Shibata 等人：“液晶各向同性相中的去极化光散射”《化学物理》杂志 109・5 2038-2042（1998 年）。

T.Sakurai et al.: "The Vibrational-Translational Energy Transfer in Binary Mixtures : Influence of the Vibrational Mode Close to the Lowest Mode Group Relaxation" Japanese Journal.Applied Physiscs. 37・5. 2805-2807 (1998)

T.Sakurai 等人：“二元混合物中的振动平移能量转移：接近最低模态群弛豫的振动模态的影响”日本期刊。应用物理学 37・5（1998）。

T.Sakurai, M.Asai, T.Matsuoka, S.Koda, H.Nomura: "The Vibrational-Translational Energy Transfer in Binary Mixtures : Influence of the Vibrational Mode Close to the Lowest Mode Group Relaxation" Japanese Journal. Applied Physiscs. 37-11. 6098-6101 (1998)

T.Sakurai、M.Asai、T.Matsuoka、S.Koda、H.Nomura：“二元混合物中的振动平移能量转移：接近最低模式群弛豫的振动模式的影响”日本期刊。