Direct methods for analyzing these specimens are classified based on if they measure real-space. Hermann–Mauguin notation was developed to describe these specimens. An electron gun is fired at one of these specimens in ultra-high vacuum, after which filtered electrons (-5[1])are measured on a hemispherical fluorescent screen in LEED. The Debye-Scherrer method allows analysis of imperfect examples of these specimens (15[1])due to being able to grind the sample to a (*) powder. When refining data from these specimens, one must identify the shape of their unit cells and subsequently their space groups. Bragg’s law describes (10[1])diffraction through, for 10 points, what solids with repeating structures? ■END■ (10[2])