Institute of Solid State Chemistry, Ural Branch, Russian Academy of Sciences, Pervomaiskaya 91, Ekaterinburg, 620990, Russia.
Ural Federal University, Mira 19, Ekaterinburg, 620002, Russia.
Sci Rep. 2017 Sep 7;7(1):10769. doi: 10.1038/s41598-017-11164-6.
The superlattice and domain structures exhibited by ordered titanium monoxide TiO are disrupted by low energy electron beam irradiation. The effect is attributed to the disordering of the oxygen and titanium sublattices. This disordering is caused by the displacement of both oxygen and titanium atoms by the incident electrons and results in a phase transformation of the monoclinic phase TiO into cubic B1 titanium monoxide. In order to determine the energies required for the displacement of titanium or oxygen atoms, i.e. threshold displacement energies, a systematic study of the disappearance of superstructure reflections with increasing electron energy and electron bombardment dose has been performed in situ in a transmission electron microscope (TEM). An incident electron energy threshold between 120 and 140 keV has been observed. This threshold can be ascribed to the displacements of titanium atoms with 4 as well as with 5 oxygen atoms as nearest neighbors. The displacement threshold energy of titanium atoms in TiO corresponding with the observed incident electron threshold energy lies between 6.0 and 7.5 eV. This surprisingly low value can be explained by the presence of either one or two vacant oxygen lattice sites in the nearest neighbors of all titanium atoms.
有序氧化钛 TiO 的超晶格和畴结构被低能电子束辐照破坏。这种效应归因于氧和钛亚晶格的无序化。这种无序化是由入射电子引起的氧和钛原子的位移引起的，导致单斜相 TiO 向立方 B1 钛氧化钼的相变。为了确定钛或氧原子的位移所需的能量，即阈位移能，在透射电子显微镜 (TEM) 中进行了系统的研究，以研究超结构反射随电子能量和电子轰击剂量的增加而消失的情况。观察到的入射电子能量阈值在 120 到 140keV 之间。这个阈值可以归因于具有 4 个和 5 个氧原子作为最近邻的钛原子的位移。与观察到的入射电子阈值能量相对应的 TiO 中钛原子的位移阈值能量在 6.0 到 7.5eV 之间。这个令人惊讶的低值可以通过所有钛原子的最近邻中存在一个或两个空位氧晶格位置来解释。
