Exotic Two-Dimensional Structure: The First Case of Hexagonal NaCl

J Phys Chem Lett. 2020 May 21;11(10):3821-3827. doi: 10.1021/acs.jpclett.0c00874. Epub 2020 May 1.


NaCl is one of the simplest compounds and was thought to be well-understood, and yet, unexpected complexities related to it were uncovered at high pressure and in low-dimensional states. Here, exotic hexagonal NaCl thin films on the (110) diamond surface were crystallized in the experiment following a theoretical prediction based on ab initio evolutionary algorithm USPEX. State-of-the-art calculations and experiments showed the existence of a hexagonal NaCl thin film, which is due to the strong chemical interaction of the NaCl film with the diamond substrate.