Heats of reaction of silicon, germanium, and tin tetrahalides with pyridine and isoquinoline

Abstract

Heats of formation of crystalline MX₄,2L complexes (where M = Si, Ge, or Sn; L = pyridine or isoquinoline; X = F, Cl, or Br, except X = Cl only when M = Sn) have been measured calorimetrically. Values decrease in the order MF₄ > MCl₄ > MBr₄, GeX₄ > SiX₄, and SnCl₄ > GeCl₄ > SiCl₄, except that those for SiCl₄,2py and SiBr₄,2py are abnormally high. Comparisons are drawn with results from other sources and attempts are made to explain the observed orders.