A long-range ordered (LRO) structure with 2a × 2a periodicity is formed in 1T-TiSe₂ flakes by electron beam irradiation. Transmission electron microscopy shows that the LRO structure is not only formed in the area irradiated by the electron beam, but also in the adjacent unirradiated area after the electron beam irradiation. We propose that the formation of the LRO structure is triggered by electron excitation to the non-bonding orbital of 1T-TiSe₂ due to inelastic electron scattering. We consider that the LRO structure is spread spontaneously to the adjacent area by a chemical chain reaction due to the electron transfer.

中文翻译：

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电子束辐照在1 T -TiSe _2中形成2 a  ×2 a长程有序结构的机理及其自发扩大

通过电子束辐照，在1 T -TiSe ₂薄片中形成具有2 a  ×2 a周期性的长程有序（LRO）结构。透射电子显微镜显示，LRO结构不仅在电子束照射的区域中形成，而且在电子束照射后的相邻未照射区域中形成。我们认为，由于非弹性电子散射，电子激发到1 T -TiSe ₂的非键合轨道触发了LRO结构的形成。我们认为由于电子转移，LRO结构通过化学链反应自发地扩散到相邻区域。