The solid state structure of tellurium tetrachloride

The structure of crystalline SeCU is similar to that of TeCU. The latter evaporates as a monomer, while SeCl4 decomposes to the dichloride and CI2. 

At the MO level, the stereochemical inactivity of the lone pair may be rationalized if it is assumed to occupy the spherically symmetrical 5s atomic orbital, while each nearly linear ChTeCU fragment is described as a 3c, 4e bonding system. 

for example N. A. Alhnger, Molecular Mechanics, in Accurate Molecular Structures, A. Dominicano and I. Hargittai, Eds., International Union of Crystallography, Oxford University Press, 1992. 

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