Synthesis and Characterization of Sodium Hexakis(Chlorosulphato)-Iridate (IV), Na2Ir(So3 cl)6 and Sodium Tetrakis(Chlorosulphato)-Palladate (II), Na2Pd(SO3Cl)4

Sodium hexakis(chlorosulphato)iridate, Na 2 Ir(SO 3 Cl) 6 and sodium tetrakis(chlomsulphato)palladate, Na 2 Pd(SO 3 Cl) 4 , have been synthesized by solvolytic reactions of the corresponding chlorides with chlorosulphuric acid. A positive shift in the sym. SO 3 stretching mode γ 1 (A) and the splitting of the E modes of the free SO 3 Cl − ion (C 3v ) indicate a C s symmetry of the SO 3 Cl − group such that each SO 3 Cl − group is covalently bonded to the central metal atom through one of the oxygen of this group. The bands obtained in the reflectance spectra and the values of magnetic moments suggest an octahedral and a square planer geometry for hexakis-(chlorosu1phato)iridate and tetrakis(chlorosulphato)palladate, respectively.