We have studied the commensurate-incommensurate phase transition, rotation epitaxy, and strain relief patterns in ${\mathrm{C}}_{60}$ overlayers grown on Cd(0001) with a low-temperature scanning tunneling microscopy. When deposited at low temperature (∼200 K), ${\mathrm{C}}_{60}$ molecules form the 10×10 high-order commensurate (HOC) phase with two different half-unit cells, resembling the $\mathrm{Si}\left(111\right)\text{−}7\times 7$ surface. Postannealing at room temperature (RT) results in the transition from HOC phase to incommensurate phase, in which strain relaxation takes place in the form of periodic vacancies and ${\mathrm{C}}_{60}$ heptamer arrays. In the case of RT deposition, parallel stripe domain walls appeared in the commensurate $2\sqrt{3}\times 2\sqrt{3}$ R30° phase. These results provide essential information for understanding the strain relaxation mechanism, and the role of substrate temperatures in the process of ${\mathrm{C}}_{60}$ thin films growth.

中文翻译：

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Cd(0001) 上单层 C60 中的相称-不相称转变和应变消除模式

我们研究了相称-不相称相变、旋转外延和应变消除模式 ${\mathrm{C}}_{60}$用低温扫描隧道显微镜在 Cd(0001) 上生长的覆盖层。当在低温（~200 K）下沉积时，${\mathrm{C}}_{60}$ 分子与两个不同的半晶胞形成 10×10 高阶相称 (HOC) 相，类似于 $硅\left(111\right)\text{-}7\times 7$表面。室温 (RT) 后退火导致从 HOC 相过渡到不相称相，其中应变弛豫以周期性空位和${\mathrm{C}}_{60}$七聚体阵列。在 RT 沉积的情况下，平行条纹畴壁出现在相称的$2\sqrt{3}\times 2\sqrt{3}$R30°相位。这些结果为理解应变弛豫机制以及衬底温度在拉伸过程中的作用提供了重要信息。${\mathrm{C}}_{60}$ 薄膜生长。