χ measurements and optical limiting studies of 2-chloro-5-nitro-N′-[(1E)-phenylmethylidene] benzohydrazide with substituents

The nonlinear optical properties of hydrazones substituted with different donor groups were studied using single beam Z-scan technique with nanosecond laser pulses at 532 nm. The nonlinear response in these molecules was found to increase with increase in the donor strength of the substituted group. The χ⁽³⁾ value of these molecules is found to be of the order of 10⁻¹³ esu. The nonlinear refractive index (n₂) of the samples is found to be negative and the largest value of n₂ obtained for the strong donor-substituted molecule is −8.83 × 10⁻¹¹ esu. All samples show good optical limiting behavior at 532 nm. The best optical limiting behavior was observed with the molecule substituted by a strong electron donor.