Abstract Here we discuss the crystal structure of solvent-free TBACl and its solvates – TBACl∙0.5C7H8, and TBACl∙xH2O, x ≈ 0.1, obtained from single-crystal X-ray diffraction experiments and DFT calculations. Solvent-free TBACl and the hydrate crystallize in P21/n space group, with the ions adopting deformed trigonal coordination and forming layers in the (1 0 1) plane. Similar coordination is observed in TBACl∙0.5C7H8, I2/a. The hydrate is stabilized by rather strong O–H⋯Cl hydrogen bond, as it is indicated by DFT optimization required for obtaining more realistic position of water molecule. According to TGA/DSC results, dry TBACl melts at 76.3 °C (onset), with a DSC peak at 79.4 °C, and vaporizes during further heating above 170 °C, decomposing into smaller fragments, as observed in the MS spectra.

中文翻译：

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无溶剂四丁基氯化铵及其新型溶剂化物的结构和热学研究

摘要 在这里，我们讨论了无溶剂 TBACl 及其溶剂化物——TBACl∙0.5C7H8 和 TBACl∙xH2O 的晶体结构，x ≈ 0.1，由单晶 X 射线衍射实验和 DFT 计算得到。无溶剂 TBACl 和水合物在 P21/n 空间群中结晶，离子采用变形三角配位并在 (1 0 1) 平面上形成层。在 TBACl∙0.5C7H8, I2/a 中观察到类似的配位。水合物通过相当强的 O-H⋯Cl 氢键稳定，正如获得更真实的水分子位置所需的 DFT 优化所表明的那样。根据 TGA/DSC 结果，干燥的 TBACl 在 76.3 °C（开始）熔化，DSC 峰值在 79.4 °C，并在进一步加热至 170 °C 以上时蒸发，分解成更小的碎片，如在 MS 光谱中观察到的那样。