There is evidence of dimerisation in the gaseous phase. The solid state structure is related to that of SnCl2 and PbCl2 and  the tin atoms have five near bromine atom neighbours in an approximately trigonal bipyramidal configuration.
In the gaseous state, dimerization has been observed. The solid-state structure shares similarities with SnCl2 and PbCl2, where tin atoms have approximately five neighboring bromine atoms arranged in a nearly trigonal bipyramid shape.