Two kinds of magnetic interactions are experimentally reported in [Cu2CI6](-) complexes, namely ferromagnetic and antiferromagnetic ones. Symmetry related magnetic interactions in these complexes have been considered. First we defined the local symmetry properties of the molecule and then we determined symmetry adapted molecular orbitals. The bonding orbitals among two Cu atoms in [Cu2Cl6](-) complexes seem to be sigma orbitals. However, the structure of these molecules indicates that a bonds must exist in these molecules.