Abstract：
In homogeneous solid-state reactions, the single-crystal nature of the starting material remains unchanged, and the system evolves seamlessly through a series of solid solutions of reactant and product. Among [2+2] photodimerizations of cinnamic acid derivatives in the solid state, those involving salts of the 4-aminocinnamic acid have been recognized to proceed homogeneously in a \"single-crystal-to-single-crystal\" fashion by X-ray diffraction techniques. Here the bromide salt of this compound class is taken as a model system in a Raman spectroscopy study at low wavelengths, to understand how such a mechanism defines the trend of the crystal lattice vibrations during the reaction. Vibrational mode calculations, based on dispersion corrected DFT simulations of the crystal lattices involved in the transformation, have assisted the interpretation of the experiments. Such an approach has allowed us to clarify the spectral signatures and to establish a correlation between the dynamics of the monomer and dimer systems in a process where chemical progress and crystal structural changes are demonstrated to occur simultaneously.
摘要：
在均相固态反应中，原料的单晶性质保持不变，该系统通过一系列反应物和产物的固溶体无缝发展。在固态肉桂酸衍生物的[22]光二聚中，通过X射线衍射技术，已经认识到涉及4-氨基肉桂酸盐的那些以“单晶到单晶”的方式均匀地进行。在低波长的拉曼光谱研究中，将该化合物类的溴化物盐作为模型系统，了解这种机制如何定义反应过程中晶格振动的趋势。振动模式计算，基于色散校正的DFT模拟的晶格参与变换，帮助解释实验。这种方法使我们能够阐明光谱特征，并在化学过程和晶体结构变化同时发生的过程中建立单体和二聚体系统动力学之间的相关性。
