Design, synthesis and nonlinear optical properties of (E)-1-(4-substituted)-3-(4-hydroxy-3-nitrophenyl) prop-2-en-1-one compounds

The variation of nonlinear absorption coefficient of the (E)-1-(4-substituted)-3-(4-hydroxy-3-nitrophenyl) prop-2-en-1-one compounds (a) with the phonon characteristic energies, Ep and (b) with the (2hν−Eg+Ep). The red line is the best fit to the data with an exponential growth function and linear function for the above two cases respectively.