Clathrate hydrates of tetrabutylammonium and tetraisoamylammonium halides

Abstract

Clathrate formation was considered for two series of systems: (C 4H9)4NG-H2O and (i-C 5H11)4 xNG-H2O (G = F-, Cl-, Br-, I-). Clathrate hydrates of tetraisoamylammonium halides were shown to melt at higher temperatures than those of the butyl series. In passing from fluoride to bromide, the stability of compounds of the butyl series falls significantly and tetrabutylammonium iodide does not produce polyhydrates. In the isoamyl series, the melting points of polyhydrates vary insignificantly for different halides. In addition, the highest melting hydrate of tetraisoamylammonium bromide melts at a slightly higher temperature than chloride hydrates, indicating that there is more than just a hydrophilic effect of the anion on clathrate formation. © 2002 Plenum Publishing Corporation.