One-dimensional atomistic holes (that is, a single vacancy-chain and bundles which penetrated a MgO film) were produced individually by convergent-beam irradiation within a high-resolution transmission electron microscope. The widths of these imperfections ranged from 0.21 to 0.42nm, and were less than that of one unit cell of the NaCl structure. The imperfections were line-type lattice defects.

A Single Vacancy Chain and its Bundle in Magnesium Oxide as Line-Type Lattice Defects. T.Kizuka, M.Kawasaki: Japanese Journal of Applied Physics - 1, 2001, 40[1], 428-9