一种有机聚合物自旋模型的磁性质  

Magnetism of An Organic Polymer Spin Model

作　　者：刘美琪[1] 李晓光[1] 梁二军[2] 

机构地区：[1]安阳广播电视大学,安阳455000 [2]郑州大学物理工程学院材料物理教育部重点实验室,郑州450052

出　　处：《河南大学学报（自然科学版）》2009年第4期353-355,共3页Journal of Henan University:Natural Science

基　　金：国家自然科学基金资助课题项目(10574113)

摘　　要：利用s=2的大自旋和s=1/2的两个π型连接的小自旋组成自旋单元模型,按照一维伊辛问题的矩阵算法处理,探讨了有机聚合物的磁性质.用计算机模拟给出在外磁场作用下铁磁相互作用和反铁磁相互作用的磁化强度与磁感应系数与温度的关系.结果表明,在反铁磁相互作用下,随着外磁场的变化低温时磁化强度有三个极限值,其中两个是稳定的,一个是不稳定的.这个不稳定的磁化强度对应于一个临界磁场,低温时外场变化经过临界磁场时磁化强度发生突变.Magnetism of an organic polymer has been studied by using matrix algorithm of one-dimension Ising problem with a spin unit model consisting of one large spin s= 2 and two nconjugated small spins s= 1/2. The relationship of the magnetization and magnetic induction coefficients with temperature for ferromagnetic and anti-ferromagnetic interactions under external magnetic field are simulated. It is shown that for anti-ferromagnetic interaction the magnetization exhibits three limiting values in low temperature with external magnetic field, two of which are stable and the other is unstable. The unstable magnetization changes discontinuously when across a critical value, corresponding to a critical magnetic field.

关 键 词：有机聚合物 自旋模型 磁化强度 磁感应系数 临界磁场 

分 类 号：O441.6[理学—电磁学]