An electroactive polyazomethine is prepared from a solution processable 2,5-diaminothiophene derivative and 4,4 ′ -triphenylamine dialdehyde by spraycoating the monomers on substrates, including indium tin oxide (ITO) coated glass and native glass slides. The conjugated polymer was rapidly formed in situ by heating the substrates at 120 ° C for 30 min in an acid saturated atmosphere. The resulting immobilized polymer is easily purifi ed by rinsing the substrate with dichloromethane. The on-substrate polymerization is tolerant towards large stoichiometry imbalances of the comonomers, unlike solution step-growth polymerization. The resulting polyazomethine is electroactive and it can be switched reversibly between its neutral and oxidized states both electrochemically and chemically without degradation. A transmissive electrochromic device is fabricated from the immobilized polyazomethine on an ITO electrode. The resulting device is successfully cycled between its oxidized (dark blue) and neutral (cyan/light green) states with applied biases of + 3.2 and − 1.5 V under ambient conditions without signifi cant color fatigue or polymer degradation. The coloration effi ciency of the oxidized state at 690 nm is 102 cm 2 C − 1 .2 was chosen as a complementary monomer for condensing with 1 . This was because the resulting polyazomethine ( 3 ) was expected to absorb more in the yellow region of the spectrum than its all-thiophene polyazomethine counterpart. [ 17 ] This is a result of large twist angles between the homoaryl moieties and the azomethines of 3 that limit its degree of conjugation. However, its charged state was expected to be signifi cantly colored because of intramolecular charge transfer courtesy of the electron rich triarylamine. [ 18 ] A bold color transition between the neutral and charged states was therefore expected for the electroactive 3 , resulting in a electrochromic material whose switching could easily be seen by the eye. This is a desired property for use in low-resolution and large area electrochromic display applications such as signs and billboards.The on-substrate polymerization of 3 was initially done using stoichiometric amounts of the complementary comonomers. These conditions were used because step-growth polymerization is known to be intolerant towards comonomer stoichiometric imbalances. [ 19 ] Only trimers and lower molecular weight oligomers are obtained when the molar ratio of the comonomers is varied by more than 1 mol%. The 1:1 mole ratio of 1 to 2 was further used to test the polymerization conditions required to produce 3 . Since this ratio was expected to yield 3 , the effect of the monomer concentration on the resulting comonomer and polymer fi lms deposited on the substrate could also be examined.The polymerization of 3 was done by spray-coating the premixed comonomer solutions onto glass substrates. The substrates were then heated between 60 and 150 ° C in a TFA saturated environment. TFA was chosen as the catalyst because of its high vapor pressure. A saturated acid atmosphe...

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An efficient cascade FRET was realized in solid state DNA-CTMA thin films using a three chromophore system without any covalent attachments. The extent of energy transfer from Cm102 to SRh was studied and found to improve eight-fold using the bridging dye Pm567.

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