Equilibrium clusters in suspensions of colloids interacting via potentials with a local minimum
Equilibrium clusters in suspensions of colloids interacting via potentials with a local minimum
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通过具有局部最小值的电势相互作用的胶体悬浮液中的平衡簇
DOI：
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
W. Cai
中科院分区：
文献类型：
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作者：
A. Baumketner;W. Cai
在简单的胶体悬浮液中，团簇是由胶体自缔合产生的各种多聚体，并与单体平衡存在。已知有两种类型的电位可以产生簇：a)由短程吸引和远程排斥之间的竞争产生的电位，其特征是全局最小值和排斥尾巴；b)纯排斥电位，具有软肩。通过计算机模拟，我们在这项工作中证明了具有局部最小值和排斥尾的势，不属于任何一种已知类型，也能够生成簇。详细的对比分析表明，新型集群形成潜力在前两者之间起着桥梁作用。新的星系团在形状上扩展，它们的聚集是由熵驱动的，就像在纯排斥系统中一样，但只是在低密度下。在高密度下，星系团与具有相互吸引和相互排斥作用的系统一样，在能量作用下坍缩和稳定。
In simple colloidal suspensions, clusters are various multimers that result from colloid self-association and exist in equilibrium with monomers.There are two types of potentials that are known to produce clusters: a) potentials that result from the competition between short-range attraction and long-range repulsion and are characterized by a global minimum and a repulsive tail and b) purely repulsive potentials which have a soft shoulder. Using computer simulations, we demonstrate in this work that potentials with a local minimum and a repulsive tail, not belonging to either of the known types, are also capable of generating clusters. A detailed comparative analysis shows that the new type of cluster-forming potential serves as a bridge between the other two. The new clusters are expanded in shape and their assembly is driven by entropy, like in the purely repulsive systems but only at low density. At high density, clusters are collapsed and stabilized by energy, in common with the systems with competing attractive and repulsive interactions.