The reaction of [(η6-arene)Ru(μ-Cl)Cl]2 and [Cp∗M(μ-Cl)Cl]2 (M=Rh, Ir) with tetradentate N,N′-donor chelating ligand viz 3,6-bis(2-thiopyridyl)pyridazine(L1) leads to the formation of mononuclear compounds as general formula [(arene)MCl(L1)]+ {M=Ru, arene=C6H6 (1); p-iPrC6H4Me (2); C6Me6 (3); Cp∗, M=Rh (4); Cp∗, M=Ir (5)} where as 4,6-bis(2′-thiopyridyl)pyrimidine(L2) and 2,3-bis(2-thiopyridyl)pyrazine(L3) leads to the formation of dinuclear compounds as general formula [{(arene)MCl}2(L)]2+ {M=Ru, L=L2, arene=C6H6 (6); p-iPrC6H4Me (7); C6Me6 (8); Cp∗, M=Rh, (9); Cp∗, M=Ir, (10) and L=L3 C6H6 (11); p-iPrC6H4Me (12); C6Me6 (13), Cp∗, M=Rh, (14) Cp∗, M=Ir (15)}, respectively. The cationic complexes have been isolated as their PF6/SbF6 salts and characterized by FT-IR, UV–Vis, 1H NMR, Mass spectroscopic methods. X-ray crystallographic studies of some representative compounds revealed that typical piano-stool geometry around the metal center with a six-membered metallocycles in which thioether ligand acts as a N,N′-chelating ligand. Variation of bridging motifs of thioether ligands is revealed that formation of mono/dinuclear complexes. The L1 ligand yielded predominantly mononuclear compounds where as L2 and L3 yielded dinuclear compounds with trans and cis isomers, respectively.