Molecular Dynamics Simulations of Polar Liquids

• Main Authors: Yeh, Yu-Ling, 葉玉玲
• Other Authors: Chung-Yuan Mou
• Format: Others
• Language: en_US
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/28993672898221167156

博士 === 國立臺灣大學 === 化學系 === 86 === Molecular dynamics simulation of water liquid is studied using TIP4P model. The H-bond patterns were analyzed with a Voronoi Polyhedra (VP) construction of the oxygen atom distributions. An asphericity parameter for VP was used to characterize the distribution of the local H-bonds. With different asphericity values, there exist the isosbestic points in the O-O radial distribution function in NVE ensemble. The spatial distribution function shows the tetrahedarl site and interstitial site distributed with distinct ratio whiling h changed. A heterogeneous bimodal distribution of local hydrogen bond patterns implies a fluctuation between high-density water and low-density water during supercooled. A bi-exponential decay of the dipolar autocorrelation function is associated with locally cooperative rotation around the H-bond axis and with rototranslational coupling motion of the water molecule in a disordered cage. It suggests liquid water can be viewed a dynamical mixture of two types of local H-bond structures.