“…7,8 There are a few studies to determine second-order NLO coefficients by EAS, but they were determined only through second-order EAS measurements detecting the components quadratically dependent on the applied electric field, i.e., third-order NLO response. [9][10][11] Theoretically speaking, second-order NLO susceptibility χ (2) can be directly determined by first-order EAS measuring a component linearly dependent on the applied electric field. In this work therefore, the second-order NLO susceptibilities of the benzoate polymers, shown in Scheme 1, were determined by the first-order EAS, and compared with values previously obtained by SHG measurements.…”