Abstract We present a comparison of two methods for assessing the second-order non-linear optical properties of Langmuir-Blodgett films. The well-known study by second harmonic generation using a high powered laser is preferred if details of the film's tilt characteristics are required. However, we show that the more convenient, low power method for electro-optic response by surface plasmon spectroscopy gives an adequate screening method for the magnitude and sign of the second-order non-linearity from Langmuir-Blodgett layers of novel materials. We describe the synthesis, deposition and assessment by these techniques of two new stilbazolium amphiphiles. These amphiphiles are designed with their principal β tensor component in opposition to our previously studied hemicyanine and thus may facilitate the formation of non-linear Langmuir-Blodgett superlattices consisting of alternating dyes.