Deptuch Aleksandra, Kozieł Marcin, Piwowarczyk Marcin, Urbańska Magdalena, Juszyńska-Gałązka Ewa
Institute of Nuclear Physics Polish Academy of Sciences, Radzikowskiego 152, PL-31342 Kraków, Poland.
Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, PL-30387 Kraków, Poland.
J Phys Chem B. 2025 Jun 26;129(25):6455-6463. doi: 10.1021/acs.jpcb.5c03603. Epub 2025 Jun 14.
The liquid crystalline compound, forming the glass of the smectic C* phase, is investigated by X-ray diffraction in the 18-298 K range. The characteristic distances within the smectic C* phase are determined, and the specific volume is estimated. The electron density profile along the smectic layer normal is inferred and compared with the results of the density functional theory calculations. Observations of the selective reflection of the visible light investigate the helical ordering within the smectic C* glass. The results indicate slow change with temperature of the smectic layer spacing, intermolecular distances, and electron density distribution below the glass transition temperature. The change in the temperature dependence of the specific volume is well below the glass transition temperature. Meanwhile, the relative range of the short-range order within the smectic layers and the helix pitch are rather constant in the glassy state.
对形成近晶C相玻璃态的液晶化合物在18 - 298 K范围内进行了X射线衍射研究。确定了近晶C相内的特征距离，并估算了比容。推断了沿近晶层法线方向的电子密度分布，并与密度泛函理论计算结果进行了比较。通过对可见光选择性反射的观察研究了近晶C*玻璃态内的螺旋有序性。结果表明，在玻璃化转变温度以下，近晶层间距、分子间距离和电子密度分布随温度缓慢变化。比容随温度的变化在玻璃化转变温度以下很小。同时，在玻璃态下，近晶层内短程有序的相对范围和螺旋螺距相当恒定。
