Structural and thermal study of solvent-free tetrabutylammonium chloride and its novel solvates

Here we discuss the crystal structure of solvent-free TBACl and its solvates - TBACl center dot 0.5C(7)H(8), and TBACl center dot xH(2)O, x approximate to 0.1, obtained from single-crystal X-ray diffraction experiments and DFT calculations. Solvent-free TBACl and the hydrate crystallize in P2(1)/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 center dot 0.5C(7)H(8), I2/a. The hydrate is stabilized by rather strong O-H center dot center dot center dot 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 degrees C (onset), with a DSC peak at 79.4 degrees C, and vaporizes during further heating above 170 degrees C, decomposing into smaller fragments, as observed in the MS spectra. (C) 2020 Elsevier B.V. All rights reserved.