(a)[CO(NH3)4][PtCl4]and[Pt(NH3)4][COCl4](b)[Pd(PPh3)2(NCs2)]and[Pd(PPh3)2(SCN)2](c)[CO(NH3)5NO3]SO4and[CO(NH3)5SO4]NO3(d)[PtCl2(NH3)4]Br2and[PtBr2(NH3)4]Cl2