wherein A and B are the same or different and are benzene, pyridone, or heterocyclic ring containing O, S, or N, R₁ and R₁′ are H, halogen, C_1-5 alkyl, nitro, ester, carboxyl, sulfo, sulfonamide, amide, sulfo ester, C_1-3 alkoxy, amino, C_1-5 alkylamino, cyano, C_1-6 alkylsulfonyl, or C_2-7 alkoxy carbonyl, R₂, R₂′, R₃, and R₃′ are the same or different and are H, substituted or non-substituted C_1-6 straight chain or branched alkyl, substituted or non-substituted C_6-18 aryl, C_2-6 straight chain or branched alkenyl, C_3-6 cycloalkenyl, or substituted or non-substituted C_3-6 cycloalkyl, R₄ is H, C_1-5 alkyl, hydroxyl, halogen, or C_1-5 alkoxy, R₅ and R₅′ are the same or different and are H, halogen, C_1-5 alkyl, nitro, C_1-3 alkoxy, amino, cyano, C_1-6 alkylsulfonyl, or C_2-7 alkoxy carbonyl, W is oxygen, sulfur, selenium, —NR, or —C(CH₃)₂, n is 1˜18, and Z₁ and Z₂ are different and are an anion or an anionic organometallic complex with −1 or −2 valence, wherein R₂ and R₃ or R₂′ and R₃′ are joined together or with a benzene to form a ring, and R bonded to nitrogen is C_1-4 alkyl.