Theoretical study of glass transition on the basis of the Free energy landscape

我研究了自由能景观(FEL)框架下的玻璃化过程。首先，我证明了构型熵由两个项组成，一个来自标准构型熵，另一个来自自由电子激光盆地之间的动力学。用自由电子激光图像研究了硬球体系的驰豫时间，结果表明，Vogel-Fulcher关系成立，驰豫时间的发散可以归因于协同重排区域的增加。利用分子动力学模拟，研究了二维Lennard-Jones-Gauss(LJG)过冷液体的玻璃形成过程，首次得到了该过程的自由电子能谱。还测定了3DLJG液体的三个特征温度，结果表明这些温度满足Odagaki规则。在自由电子激光图像的基础上分析了高聚物的介电松弛，结果表明，仅从介电松弛就可以确定三个特征温度。

I studied the vitrification process on the bas is of the free energy landscape (FEL) framework. First, I showed that the configurationalentropy consists of two terms, one from the standard configurational entropy and the other from the dynamics among the basins of the FEL. The relaxation time of the hard sphere system is investigated using the FEL picture and it is shown that the Vogel-Fulcher relation holds and the divergence of the relaxation time could be attributed to the increase of the cooperatively rearranging region. Using the MD simulation, I also studied the glass forming process of the 2D Lennard-Jones-Gauss(LJG) super cooled liquid and obtained for the first time the FEL for the process. I also determined the three characteristic temperatures of the 3D LJG liquid and showed that these temperatures satisfy the Odagaki-rule. The dielectric relaxation of high polymers was analyzed on the basis of the FEL picture and it was shown that three characteristic temperatures could be determined from the dielectric relaxation alone.