高温高压环境下C_(60)的相变研究

高温高压环境下,C60分子之间发生聚合反应,邻近的C60分子间相对的两个六边形上的双键打开,通过[2+2]加环反应在C60分子之间形成sp3杂化键。聚合物的聚合链的维度及相结构和所加的压力与温度有关,X-ray衍射(XRD)花样研究表明,在不同的压力和温度条件下主要形成3种不同的有序结构,一维正交相orthorhombic(1D-O)、二维四方tetragonal(2D-T)和二维菱形相rhombohedral(2D-R),更高的压力和温度将导致C60分子球笼的毁坏而形成超硬相结构,为研究铁磁相的C60聚合物提供一定的参考价值。

Study on the Phase Transition of C60 under High Temperature and Pressure

C60 molecules would be polymerized under high temperature and pressure conditions. The parallel double bonds were broken and reformed as single sp^3 bonds between adjacent fullerene molecules via [2＋2] cycloaddition reaction. The dimension of the polymeric chains and the crystal structure of the polymers were relevant to the temperature and pressure conditions. The XRD patterns showed that the crystal structures of the polymeric phases had been identified as one-dimensional orthorhombic （1D-O）, two-dimensional tetragonal （2D-T）, and 2D-rhomboherdral （2D-R）. The treatment of C60 under highly non-uniform pressure and temperature resulted in the distortion of C60 cages and production of several disordered polymeric phases, which had practical reference value for the study of magnetic C60 polymers.