A molecular bonding theory for liquid thallium–tellurium alloys

Abstract

A theory is derived for the dependence of the equilibrium concentration of broken Te–Te bonds on temperature and composition, which is appropriate for a mixture of chain molecules in which each chain is terminated by a dangling bond or a monovalent atom like thallium. This is done by extending the well-established theory of Flory and others for chain polymer equilibrium to the case where there is a large concentration of chain stoppers. Ring formation is advanced as a possible factor at low temperatures and low concentrations of thallium, and the implications of this phenomenon are examined. The behaviour of the vapour pressure of tellurium is also examined, since this should be a readily measured parameter. Finally, we consider the relationship of the chain model to other structures which have been suggested for pure liquid tellurium.