The molecule of the red title compound, trans-tetra-(chloro/bromo)bis(
triphenylphosphine oxide-O)rhenium(IV), [ReBr2.5Cl1.5{OP(C6H5)(3)}(2)]
, lies on a crystallographic centre of symmetry. Coordination of rheni
um by the four halides is square planar, capped by two mutually-trans
triphenylphosphine oxide groups.