Nurture over Nature: Striking Difference in Chromic Behavior between Congeneric N-Salicylidene-4-haloanilines in Different Molecular Environments of Crystal

Two Schiff base compounds that differ only in halogen substituent (Cl or Br) showed contrasting chromic properties. By exchanging their molecular environments in the crystal, the molecules exhibited a photo-response opposite to the initial state, clearly demonstrating the importance of the environment over molecular nature. Crystal structure analysis and single-crystal microscope absorption and emission spectra of the compounds were presented in this paper.