T. Yamamoto et al., PI-CONJUGATED CHARGE-TRANSFER POLYMER CONSTITUTED OF ELECTRON-DONATING THIOPHENE AND ELECTRON-WITHDRAWING QUINOXALINE, Chemistry Letters, (9), 1994, pp. 1709-1712
Palladium-catalyzed polycondensation between 2,5-bis(trimethyl-stannyl
)thiophene and 5,8-dibromoquinoxaline derivatives gives soluble new pi
-conjugated polymers, which exhibit absorption bands at 575 +/- 30 nm
assignable to intramolecular charge transfer bands and show the three-
photon resonant third-order nonlinear optical susceptibility chi((3))
of about 5 X 10(-11) esu.