Ihn K J, Zasadzinski J A, Pindak R, Slaney A J, Goodby J
Science. 1992 Oct 9;258(5080):275-8. doi: 10.1126/science.258.5080.275.
Freeze-fracture transmission electron micrographs of the smectic A() phase confirm the twist grain boundary model of Renn and Lubensky. The fracture surface has an undulating structure with a 0.5-micrometer helical pitch parallel to 4.1-nanometer smectic layers. The layers are disrupted by a lattice of screw dislocations oriented normal to the helical axis. Optical diffraction shows that rotation of smectic blocks occurs in discrete steps of about 17 degrees ; hence, the screw dislocations are 14 to 15 nanometers apart and the grain boundaries are 24 nanometers apart. These observations show that the SmA() phase is the liquid-crystal analog of the Abrikosov phase in superconductors.
近晶A（）相的冷冻断裂透射电子显微镜照片证实了伦恩和卢本斯基的扭曲晶界模型。断裂表面具有起伏结构，其平行于4.1纳米近晶层的螺旋间距为0.5微米。这些层被垂直于螺旋轴定向的螺旋位错晶格所破坏。光学衍射表明，近晶块的旋转以约17度的离散步长发生；因此，螺旋位错相隔14至15纳米，晶界相隔24纳米。这些观察结果表明，近晶A（）相是超导体中阿布里科索夫相的液晶类似物。
