Shishkina Svitlana V, Baumer Vyacheslav N, Kovalenko Sergiy M, Trostianko Pavel V, Bunyatyan Natalya D
Department of X-ray Diffraction Study and Quantum Chemistry, SSI Institute for Single Crystals NAS of Ukraine, 60 Nauky Avenue, Kharkiv 61001, Ukraine.
Department of Inorganic Chemistry, V. N. Karazin Kharkiv National University, 4 Svobodi sq., Kharkiv 61022, Ukraine.
ACS Omega. 2021 Jan 25;6(4):3120-3129. doi: 10.1021/acsomega.0c05516. eCollection 2021 Feb 2.
Crystallization of concomitant polymorphs is a very intriguing process that is difficult to be studied experimentally. A comprehensive study of two polymorphic modifications of acetyl 2-(-(2-fluorophenyl)imino)coumarin-3-carboxamide using quantum chemical methods has revealed molecular and crystal structure dependence on crystallization conditions. Fast crystallization associated with a kinetically controlled process results in the formation of a columnar structure with a nonequilibrium molecular conformation and more isotropic topology of interaction energies between molecules. Slow crystallization may be considered as a thermodynamically controlled process and leads to the formation of a layered crystal structure with the conformation of the molecule corresponding to local minima and anisotropic topology of interaction energies. Fast crystallization results in the formation of a lot of weak intermolecular interactions, while slow crystallization leads to the formation of small amounts of stronger interactions.
伴随多晶型物的结晶是一个非常有趣的过程，很难通过实验进行研究。使用量子化学方法对乙酰基2 -（-（2 - 氟苯基）亚氨基）香豆素-3 - 甲酰胺的两种多晶型变体进行的全面研究揭示了分子和晶体结构对结晶条件的依赖性。与动力学控制过程相关的快速结晶导致形成具有非平衡分子构象和分子间相互作用能更各向同性拓扑结构的柱状结构。缓慢结晶可被视为热力学控制过程，并导致形成具有对应于局部最小值的分子构象和相互作用能各向异性拓扑结构的层状晶体结构。快速结晶导致形成许多弱分子间相互作用，而缓慢结晶导致形成少量较强的相互作用。
