Assoud Lahcen, Messina René, Löwen Hartmut
Institut fur Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universitat Dusseldorf, Universitatsstrasse 1, D-40225 Dusseldorf, Germany.
J Chem Phys. 2008 Oct 28;129(16):164511. doi: 10.1063/1.2996515.
The zero-temperature phase diagram of binary mixtures of like-charge particles interacting via a screened Coulomb pair potential is calculated as a function of composition and charge ratio. The potential energy obtained by a Lekner summation is minimized among a variety of candidate two-dimensional crystals. A wealth of different stable crystal structures is identified including A, B, AB(2), A(2)B, and AB(4) structures [A (B) particles correspond to large (small) charge.] Their elementary cells consist of triangular, square, or rhombic lattices of the A particles with a basis comprising various structures of A and B particles. For small charge asymmetry there are no intermediate crystals besides the pure A and B triangular crystals. The predicted structures are detectable in experiments on confined mixtures of like-charge colloids or dusty plasma sheets.
通过屏蔽库仑对势相互作用的同电荷粒子二元混合物的零温相图，作为成分和电荷比的函数被计算出来。通过莱克纳求和得到的势能在各种候选二维晶体中被最小化。识别出了大量不同的稳定晶体结构，包括A、B、AB₂、A₂B和AB₄结构[A（B）粒子对应大（小）电荷]。它们的原胞由A粒子的三角形、正方形或菱形晶格组成，其基包含A和B粒子的各种结构。对于小电荷不对称性，除了纯A和B三角形晶体外没有中间晶体。预测的结构在同电荷胶体或尘埃等离子体片的受限混合物实验中是可检测的。
