The effect of solvent on the excited vibronic states and first hyperpolarizability of “push–pull” merocyanines

Synthesis, linear & non linear optical (NLO) properties of some indoline based chromophores

“…As the relative intensities of both the high energy shoulder and the main absorption band showed no variation across a range of concentrations this confirms that the shoulder is not due to H-aggregation. Rather as Leng et al reported for compounds 29 and 30 [24] and as Smith et al demonstrated for compounds 2 and 31 [17], the blue-shifted shoulders observed in low polar solvents are associated with excited vibronic states. It is therefore concluded that the high energy shoulders observed in chloroform are also due to excited vibronic states, and not to aggregation.…”

“…The coloured powder was washed with copious hot water and a few small portions of cold iso-propyl alcohol to yield the crude product as a coloured solid. (17) Olive green solid (30%). Recrystallization (dichloromethane:hexanes, 1:1) afforded an olive green powder, m.p.…”

Synthesis, Structural and Nonlinear Optical Properties of 2-(3-Cyano-4-{5-[1-(2-Hydroxyethyl)- 3,3-Dimethyl-1,3-Dihydro-Indol-2-ylidene]-Penta-1,3-dienyl}-5,5-Dimethyl-5 H -Furan-2-ylidene)-Malononitrile

“…The synthesis of the chromophore (Compound 5; Scheme 1) builds on a method we have previously used to prepare compounds containing the CTF acceptor unit and conjugated spacers of varying length between the donor and the acceptor units [5,6,8,9]. The N-2-hydroxyethyl indolinium iodide salt (Compound 3) was synthesized by reaction of 2,3,3-trimethyl-3H-indole with 2-iodoethanol in acetonitrile following the general procedure reported by Wang et al [10].…”

Preparation of the Inclusion Complex-Type Nonlinear Optical Polymer

“…ey possess delocalized -electron systems capable of exhibiting charge transfer resonances, which leads to a preferential orientation of the molecules along the applied electric �eld [31][32][33]. Experimental values of dipole moments and �rst-order hyperpolarizability were reported for various PMs [34][35][36][37]. Replacing the benzopyryl moiety by 1,3-diethylthiobarbituric acid, the indoline-based PM exhibits a negative value ( 3 esu) and a dipole moment of 7.…”