Spiteri Ludovic, Messina René
Université de Lorraine, Equipe BioPhysStat, IJB FR CNRS 2843, 1 Boulevard Arago, 57070 Metz, France.
Phys Rev Lett. 2017 Oct 13;119(15):155501. doi: 10.1103/PhysRevLett.119.155501. Epub 2017 Oct 12.
We report a new phase called clinohexagonal prism (CHP) that accounts for all the ground states of dipolar hard spheres prepared at any density. This phase merely consists of an oblique prismatic lattice with a hexagonal base. Our calculations show that at intermediate densities, a special close packed body-centered orthorhombic phase coincides with the CHP phase in the ground state for a wide density window. In the high packing regime, i.e., in the vicinity of the density of the hexagonal close packed phase, it is a limiting case of the CHP phase with vanishing obliquity that emerges. These findings provide a unified and clarified view of the solid-solid transitions occurring at zero temperature in dipolar systems and should be relevant in other related molecular or soft matter systems governed by anisotropic (and possibly isotropic) soft potentials.
我们报告了一种称为斜方六棱柱（CHP）的新相，它涵盖了在任何密度下制备的偶极硬球的所有基态。该相仅由一个具有六边形底面的斜棱柱晶格组成。我们的计算表明，在中等密度下，对于较宽的密度窗口，一种特殊的密堆积体心正交相在基态下与CHP相重合。在高堆积状态下，即在六方密堆积相密度附近，出现的是倾斜度消失的CHP相的极限情况。这些发现为偶极系统中零温度下发生的固-固转变提供了统一且清晰的观点，并且在由各向异性（可能还有各向同性）软势主导的其他相关分子或软物质系统中应该也具有相关性。
