Pd n compounds

In 1922 the planar structure of the ions PdCl and PtCl was proved by the determination of the structures of the potassium salts. The coplanar arrangement of four bonds from Pd(n) and Pt(il) has since been demonstrated in many crystals. Binary compounds (chlorides, oxides, sulphides, etc.) are dealt with elsewhere here we give examples of finite molecules and ions. 

2 -dipyridyl imine complex (c), in which there is interference between the H atoms, the bond arrangement around Pd remains square planar and the ligands distort, in contrast to the Ni methenato complex mentioned earlier (p. 968). 

Palladium forms complexes such as the dithio-oxalate ion, Pd(N2S2H)2, glyoximes, and phthalocyanine which are structurally similar to the compounds of Ni and Pt, and also numerous bridged compounds. Early X-ray studies established the planar trans configuration of (d) and (e)  

Examples of the rare compounds in which Pd(ii) does not form square coplanar bonds include [PdAlCl4(C6H6)] j and [PdAl2Cl7(C6H6)] j which are formed when AICI3, A1 metal, and PdClj are reacted together in boiling benzene/ The molecules have the structures sketched at (f) and (g). These molecules are notable 

---