Monolayer crystals, often being referred as 2D crystals or 2D materials, possess the unique characteristic of having a single layer of regular atomic structure. And the more regular the structure is, the higher quality the crystal. In some cases, the atomic structure is repeated to perfection, but most of the time—as is usually the case in nature—there are some flaws.
Click here for original story, Scientists now able to map defects in 2D crystals in liquid
Source: Phys.org