Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition  

作　　者：WANG Haijun1,2, HONG Xiaozhong3, GU Fang1 & BA Xinwu1 1. College of Chemistry and Environment Science, Hebei University, Baoding 071002, China 2. International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, China 3. College of Physics Science and Technology, Hebei University, Baoding 071002, China 

出　　处：《Science China Chemistry》2006年第6期499-506,共8页中国科学（化学英文版）

基　　金：This work was supported by the National Natural Science Foundation of China (Grant Nos. 20303006 and 20574016); the Natural Science Foundation of Hebei Province (Grant Nos. B2006000959 and B2004 000093);the Natural Science Foundation of Education Committee of Hebei Province (Grant No. 2003101).

摘　　要：The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关 键 词：hydrogen BONDING fluid  EQUILIBRIUM free energy  GEOMETRICAL phase transition. 

分 类 号：O641.1[理学—物理化学]