The future development of advanced molecular systems with controlled rotation requires the development of an effective methodology for assessing the rotational performance of artificial machine components. We identified two patterns of the dielectric behavior for polar rotators in a static non-polar framework of sizable crystal showing relations between the spectral and molecular-level features of solid-state rotary motion. Various functionalization of phenylene rotors with a fluorine atom(s) changed rotational performance from high to low with rotational barriers ranging from 6.06 to 11.84 kcal mol⁻¹. The meta-F-substitution favored rotator-rotator contacts allowing for the implementation of fast rotary motion. Contrary, the presence of rotator-stator contacts inhibited independent rotator dynamics leading to opposite spectral behavior in terms of temperature evolution of loss peak amplitude. Our observations, supported by an analysis based on an asymmetric double well-potential model, show that easily noticeable spectral differences encoded some molecular-level information important for the implementation of rotary motion.

中文翻译：

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介电响应中编码的固态旋转运动图像


具有受控旋转的先进分子系统的未来发展需要开发一种有效的方法来评估人造机器部件的旋转性能。我们在相当大的晶体的静态非极性框架中确定了极性旋转器介电行为的两种模式，显示了固态旋转运动的光谱和分子级特征之间的关系。具有氟原子的亚苯基转子的各种功能化将旋转性能从高改变到低，旋转势垒范围从6.06到11.84 kcal mol ^-1 。间位F取代有利于旋转体-旋转体接触，允许实现快速旋转运动。相反，转子-定子接触的存在抑制了独立的转子动力学，导致在损耗峰值幅度的温度演化方面出现相反的光谱行为。我们的观察结果得到了基于不对称双阱电势模型的分析的支持，表明容易注意到的光谱差异编码了一些对于旋转运动的实现很重要的分子级信息。