Open AccessAN X-RAY STUDY OF MESOPHASE OF BOWL-LIKE COMPOUNDS
Author(s) -
Xin-Jiu Wang,
JingTai Zhao,
Cheng Hong-Fei,
Tao Kun,
Liangyu Wang,
Xuefeng Pei
Publication year - 1988
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.37.1729
Subject(s) - triclinic crystal system , mesophase , materials science , asymmetry , crystallography , diffraction , ferroelectricity , x ray , molecule , x ray crystallography , orientation (vector space) , position (finance) , range (aeronautics) , crystal structure , condensed matter physics , optics , liquid crystal , physics , chemistry , organic chemistry , composite material , geometry , optoelectronics , quantum mechanics , dielectric , mathematics , finance , economics
We have found that some bowl-like compounds can form disordered crystalline phaseswhich have long-range positional order, with strong fluctuation in position and orientation. Their side chains are in a molten state. X-ray diffraction has shown that two homologues of hexaesters of cyclotricatechylene are stacked as triclinic system with space group of Pl. The parameters of a unit cell, density of the compounds, as well as expansion coefficient are obtained. The modelling of an unit cell is presented, which confirms the up and down asymmetry in the molecules, but there is no ferroelectricity macroscopically.