在半金属表面上应力诱导的红荧烯晶态薄膜

Strain-driven formation of rubrene crystalline films on Bi(001)

报道了在Bi(001)衬底上从第一层开始形成的红荧烯晶体薄膜.随着覆盖度的增加,红荧烯薄膜的结构会发生从自组装到混合相的转变.在混合相中存在着红荧烯的晶体畴和分子自组装形成的畴壁.特别是,我们在这种晶体畴中发现了Kurdjunov-Sachs(KS)转动外延和巨大的压缩应力.随着覆盖度的增加,红荧烯薄膜会按照逐层生长的模式进行,直至第四个分子单层.我们认为,转动外延过程中所产生的巨大压缩应力是导致晶态红荧烯薄膜的形成原因.

We report the formation of rubrene crystalline films on Bi（001） substrate starting from the very first layer.With coverage increasing,rubrene shows a structural evolution from self-assembled monolayer to a composite phase,which consists of rubrene crystalline domains and self-assembled domain walls.In particular,Kurdjunov-Sachs（KS） rotational epitaxy has been found in rubrene crystalline domains,which reveal large compressive strains.Further deposition of rubrene leads to a layer-by-layer growth of crystalline films up to the fourth layer.The driving force for rubrene crystallinity in monolayer regime has been attributed to the anisotropic strains generated in KS rotation epitaxy.