C60单晶的表面形貌与生长缺陷

用气相法生长出了毫米尺寸的具有规则晶面和金属光泽的高质量的纯C₆₀单晶.X射线衍射分析表明,C₆₀单晶在室温下具有面心立方(fcc)结构,晶格常数为α=1.4199(4)nm。用扫描电子显微镜和光学显微镜观察了C₆₀单晶的形貌,除观察到fcc结构的晶体所特有的{111}和{200}两种稳定晶面以及非常容易形成的孪晶之外,还发现了在{111}面上的树枝状、垄状和生长丘以及在{200}面上的树枝状、游泳池状和生长丘的生长缺陷。对C_{60 关键词：}

MORPHOLOGY AND GROWTH DEFECTS OF C60 CRYSTALS

Millimeter-sized C₆₀ single crystals with regular, shiny and smooth faces were grown from vapor phase. The structure of C₆₀ crystals was confirmed to be face-centered-cubic (fcc, a = 1. 4199(4) nm) by X-ray diffraction at room temperature. The morphologies and growth defects were studied by both the scanning electron microscope and the optical microscope. In addition to the typical stable {111} and {200} faces and twins for fcc crystals, we also observed the dentrites,ridge like defects and growth hillocks on {111} faces and dentrites,growth hillocks and swimming-pool-like defects on {200} faces. The morphologies appeared were compared with the theoretical equilibrium forms. The mechanism of the formation of the growth defects were analysed. The effects of growth conditions on the growth morphology of C₆₀ crystals were discussed. These results will be helpful for the investigation or the growth mechanism of C₆₀ single crystals by vapor transport method.