The electrochemical polymerization and characterization studies were made forrnmonomers: 3',4'-Diamino-2,2':5',2''-terthiopene (L1), 3',4'-bis(2-iminomethylphenol)-rn2,2':5',2''-terthiopene (L2), [NiCl(H2O)3{3',4'-diamino-2,2':5',2''-terthiopene }] chloridernhexahydrate (C1), [ZnCl2(H2O)2{3',4'-diamino-2,2':5',2''-terthiopene }] dehydrate (C2),rn[2NiCl2H2O {3',4'-bis(2-iminomethylphenol)-2,2':5',2''-terthiopene}]tetrahydrate (C3)rnand [Zn(NH3)2{3',4'-bis(2-iminomethylphenol)- 2,2':5',2''-terthiopene}] (C4) inrnEt4NBF4/CH3CN solution using glassy carbon and platinum as working electrodes,rnAg/AgCl as reference electrode and platinum as counter electrode. When the potentialrnwas scanned between 0.0 and1.6 V for L1 and L2 as well as -0.3 to 1.1V for C1 and C2,rnthey polymerize in ï¡,ï¡''-linked polyterthiophene systems except L2 which displays bothrnphenylene and thienylene linkages. However, C3 and C4 do not polymerize between 0.0rnand 1.6V. The polyterthiophene films prepared have further been cycled inrnEt4NBF4/CH3CN solution to check their electrochemical stability. Metal containingrnpolymer films (C1 and C2) exhibit better cycling behavior than polymers of L1, and L2.rnReduction of nickel from Ni+2 to Ni+1 was proposed during the first five cycles.rnKey words: Et4NBF4/CH3CN, ï¡ , ï¡ ''-linked polyterthiophene, 3',4'-Diamino-2,2':5',2''-rnterthiopene(L1), 3',4'-bis(2-iminomethylphenol)- 2,2':5',2''-terthiopene(L2), [NiCl(H2O)3rn{3',4'-diamino-2,2':5',2''-terthiopene}] chloridehexahydrate(C1), [ZnCl2(H2O)2{3',4'diamirnno-2,2':5',2''-terthiopene }] dihydrate(C2), [2NiCl2H2O{3',4'-bis(2-iminomethylphenol)-rn2,2':5',2''-terthiopene}] tetrahydrate(C3) and [Zn(NH3)2{3',4'-bis(2-iminomethylphenol)-rn2,2':5',2''-terthiopene}] (C4