权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Theory of glass transition in the energy landscape picture and nonequilibrium statistical physics

能量景观图中的玻璃化转变理论与非平衡统计物理

基本信息

批准号：
13640389
负责人：
ODAGAKI Takashi
金额：
$ 2.24万
依托单位：
Kyushu 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-13640389/
关键词：
Glass transition Mode coupling theory Energy landscape Scaling of specific heat Diatomic molecular supercooled liquid Molecular simulation Trapping diffusion model Johari-Goldstein process 協調緩和領域アダム・ギブズ理論ランドスケープ比熱アニールド平均クエンチ

项目摘要

1. First observation of the cooperatively rearranging region was made for the supercooled liquid of soft-core discs.2. Using the newly developed frame work to obtain the specific heat of non-equilibriun system described by the energy landscape picture, the temperature dependence of the specific heat was obtained for various cooling process for a model energy landscape and it was shown that the anomaly at the glass transition point is explained by the transition from the annealed to the quenched average.3. A new order parameter, the degree of annealing, was introduced and was shown to be effective in describing the glass transition.4. Employing the power law distribution for the jump rate between basins in the energy landscape, we showed that the specific heat anomaly at the glass transition is comoatible with experiments.5. Relaxation process in the supercooled state of various modes of diatomic molecule were investigated by the molecular dynamics simulation and it was shown that coupling between rotational, bibrational and translational motions gives rise to the Johari-Goldstein process and the high frequency wing.6. A non-Gaussian parameter in the frequency domain was introduced and its behavior near the glass transition was investigated. Using the wave number dependence of the relaxation time we developed a new method to distinguish the homogeneous and non-homogeneous pictures for the slow relaxation.

1.首次观测到软核过冷液的协同重排区。利用新开发的框架获得了由能量景观图描述的非平衡体系的比热，得到了模型能量景观中不同冷却过程的比热随温度的变化关系，表明玻璃转变点处的反常现象是由退火态到淬火态的平均转变来解释的。引入了一个新的有序参数--退火度，该参数可以有效地描述玻璃化转变。利用能量格局中盆地间跳跃率的幂函数分布，我们证明了玻璃化转变处的比热异常与实验结果一致。通过分子动力学模拟研究了双原子分子过冷态的驰豫过程，结果表明，转动运动、双振动运动和平移运动之间的耦合导致了Johari-Goldstein过程和高频翼的产生。在频域中引入了一个非高斯参数，并研究了它在玻璃化转变附近的行为。利用弛豫时间与波数的关系，我们发展了一种新的方法来区分慢弛豫的均匀图像和非均匀图像。