(Z)-α-cyano-β-(N-hexadecylquinolin-4-ylium)-4- styryldicyanomethanide, C16H33-Q3CNQ, has two Langmuir-Blodgett (LB) phases that differ in thickness, tilt angle and second-order susceptibility. For phase I, I = 2.2nm layer-1, φ = 8° and χzzz(2) = 180 pm V-1 at 1.064 μm, whereas for phase II, I = 1.6 nm layer-1, φ = 24° and χzzz(2) = 100 pm V-1. The susceptibility of phase I is the highest so far reported for an LB multilayer; the structure is non-centrosymmetric (Z-type) and, as predicted by theory, the second-harmonic intensity varies as I2ω(N) = I2ω(1)N 2 as N increases from 1 to 200 layers. In contrast, C 10H21-Q3CNQ has a low susceptibility (χ zzz(2) = 6 pm V-1) and neutron reflectivity studies have indicated an antiparallel alignment of chromophores at the air/water interface.
|Number of pages||6|
|Journal||Journal of Materials Chemistry|
|Publication status||Published - 1995|
ASJC Scopus subject areas
- Materials Science(all)
- Materials Chemistry
- Physical and Theoretical Chemistry