高等研究院Institute forAdvanced Study
高等研究院2016-2017学年名师讲堂(第二十二期)
Electrostatics beyond Poisson-Boltzmann: Effects of Self-Energy
Prof. Dr. Zhen-Gang Wang
Division of Chemistry and Chemical Engineering, California Institute of Technology
About the Speaker
王振纲教授1982年毕业于北京大学到美国攻读学位,1987年获芝加哥大学博士学位后,分别在Exxon公司和加州大学洛杉矶分校做博士后研究。1991年受聘于美国加州理工学院化学与化工学部,现为Lawrence A. Hanson Jr.讲座教授。王振纲教授是国际知名的高分子和软物质理论物理学家。主要研究领域涉及高分子溶液、混合物和共聚物的热力学与动力学;表面和界面;液晶态、胶体和凝胶;软物质体系的静电相互作用;DNA和RNA的生物物理和病毒自组装;生物膜物理等。在国际核心期刊上发表研究论文一百四十余篇,多次应邀在美国化学会年会、美国物理学会年会等重大国际会议上做报告。2001年当选美国物理学会会士。王振纲教授在高分子和软物质物理及其相关领域理论造诣深厚,特别谙熟热力学、统计力学和高分子物理的基础理论和基本内容,在美国加州理工学院以无教案全程讲授这三门课程而著名,2008年获美国加州理工学院最高教学奖-Richard P. Feynman奖。
Talk Introduction
Ions are essential in physical chemistry, colloidal science, electrochemistry, biology and many other areas of science and engineering. While their role is commonly described in terms of screening and translational entropy, many phenomena, ranging from some classical experimental observations made many decades ago to some new systems of current interest, cannot be explained, even qualitatively, by these concepts. A key effect that is often ignored or inadequately treated in the main literature on electrolytes and polyelectrolytes is the self-energy of the ions. In this talk, I will discuss several self-energy effects in macromolecular and interfacial systems. First, we show that the preferential solvation energy of the ions provides a significant driving force for phase separation. This concept is used to develop a theory to explain the dramatic shift in the order-disorder transition temperature in PEO-PS diblock copolymers upon the addition of salt. Second, we show that the dielectric contrast between the polymer backbone and the solvent significantly affects the conformation and charge condensation in dilute polyelectrolyte solutions. Third, we show that the image force has qualitative effects on the double layer structure and forces, such as like charge attraction and charge inversion. Finally we present a simple theory for treating charge correlation effects in polyelectrolyte solutions that self-consistently account for the conformation changes of the polyelectrolyte chains.
时间:2017年9月1日15:00-16:30
地点:南图书馆报告厅
All are welcome!