Vapor-Deposited Glasses with Long-Range Columnar Liquid Crystalline Order
Vapor-Deposited Glasses with Long-Range Columnar Liquid Crystalline Order
复制标题
DOI：
10.1021/acs.chemmater.7b02852
复制
发表时间：
2017-11-14
影响因子：
8.6
通讯作者：
Ediger, M. D.
中科院分区：
文献类型：
--
作者：
Gujral, Ankit;Gomez, Jaritza;Ediger, M. D.
各向异性分子堆积，特别是在高度有序的液晶排列中，在有机电子和光电子应用中具有优化性能的潜力。在这里，我们展示了物理气相沉积可以用来制备盘状液晶系统的高度有序的玻璃固体。利用掠入射X射线散射、原子力显微镜和紫外可见光谱，我们比较了三种体系：矩形柱状液晶、六方柱状液晶和非介晶。对于液晶系统，可通过气相沉积获得的堆积基元是高度有序的，其柱子在面内或面外传播取决于沉积过程中的衬底温度。在给定的衬底温度下形成的结构可以理解为在沉积过程中向平衡液晶表面的结构部分平衡的结果。
Anisotropic molecular packing, particularly in highly ordered liquid crystalline arrangements, has the potential for optimizing performance in organic electronic and optoelectronic applications. Here we show that physical vapor deposition can be used to prepare highly organized glassy solids of discotic liquid crystalline systems. Using grazing incidence X-ray scattering, atomic force microscopy, and UV vis spectroscopy, we compare three systems: a rectangular columnar liquid crystal, a hexagonal columnar liquid crystal, and a nonmesogen. The packing motifs accessible by vapor deposition are highly organized for the liquid crystalline systems with columns propagating either in-plane or out-of-plane depending upon the substrate temperature during deposition. The structures formed at a given substrate temperature can be understood as resulting from partial equilibration toward the structure of the equilibrium liquid crystal surface during the deposition process.