Optical chirality of citronelloxy-cyanobiphenyl monolayer at an air–water interface studied by the MDC and SHG measurement

Chirality of S- and R-enantiomer of citronelloxy-cyanobiphenyl (CCB) monolayer on a water surface were investigated by Maxwell displacement current (MDC) and optical second harmonic generation (SHG) measurements. While p–s SHG signal could not reveal the presence of chirality, the polarized angle dependence measurement indicated the ratio between chiral and achiral component of the non-linear optical susceptibility as (χxyz + χxzy)/(χxxz + χxzx) ≈ 1/40 and ≈1/23 for S- and R-CCB, respectively. It was confirmed that our MDC–SHG system has the ability to detect the chirality in monolayer level.