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Isolation of E-1,2-bis(4-bromophenyl)-1,2-diphenyl-ethylene from the E/Z isomer mixture obtained by a McMurry coupling reaction and reaction of this isomer with imidazole followed by N-alkylation with nBuBr and anion exchange yielded the bisimidazolium tetraphenylethylene(TPE)derivative H2-E-1(PF6)2.The reaction of H2-E-1(PF6)2 with Ag2O yielded the di-nuclear metallarectangle[Ag2(E-1)2](PF6)2 where the two bis-NHC donors E-1 bridge two silver atoms.Irradiation of[Ag2(E-1)2](PF6)2 leads to E/Z isomerization of the di-NHC ligand and formation of Z-1 in the mononuclear complex[Ag(Z-1)]PF6.Demetallation of the di-NHC ligand with NH4Cl/NH4PF6 yielded bisimidazolium salt H2-Z-1(PF6)2.The unique isomerization of the E-TPE derivative into its Z-isomer via metal complex formation/irradiation/demetallation cannot be achieved by irradiation of the individual imidazolium salt.The emissive properties of the TPE complexes[Ag2(E-1)2](PF6)2 and[Ag(Z-1)]PF6 have been investigated.