摘要
准晶的高分辨电子显微像常显示为直径为 2nm、呈十重对称的圆盘 ,它们还经常重叠 .据此 ,Gummelt在1995年设计出一种内部涂有两种颜色的正十边形 ,并且证明只要在覆盖时两个十边形中同一颜色的部分相重 ,就会给出准周期的Penrose图 .这种覆盖理论只需要一种正十边形的“准单胞” ,覆盖部分是相邻“准单胞”生长的核 .覆盖越多 ,结构越稳定 .Gummelt在 1999年将正十边形中的两种颜色去掉 ,既可给出准周期结构 ,也可给出周期结构 。
The high\|resolution electron microscopic images of quasicrystals very often show overlapped decagonal discs of about 2nm in diameter.Based on this observation,Gummelt in 1995 designed a two\|coloured decagon which can be overlapped with neighbouring ones.If the covering region of two decagons has the same coloured parts,it can be proven that this covered pattern,like Penrose pattern,is a quasiperiodic one.Such a quasiperiodic covering requires only one “quasi\|unit cell” and the covered region serves as a nucleus of the formation of the neighbouring “quasi\|unit cell”.Gummelt in 1999 removed the colour in the decagon,and such a covered pattern could be periodic,quasi\|periodic,or something intermediate between them.
出处
《物理》
CAS
2000年第12期708-711,共4页
Physics
基金
国家自然科学基金!(批准号 :59772 0 1 5)资助项目
关键词
准晶
十边形
覆盖
近似晶体相
quasicrystal,decagon,covering,approximant
