2,4,6-Trinitro-<i>N</i>-(<i>m</i>-tolyl)aniline: A New Polymorphic Material Exhibiting Different Colors

2,4,6-Trinitro-N-(m-tolyl)aniline or N-picryl-m-toluidine (abbreviated as TMA), exhibiting color polymorphism, was synthesized and characterized structurally, spectroscopically, thermodynamically. The studies consider both the isolated molecule of compound (studied theoretically at DFT(B3LYP)/6-311++G(d,p) level experimentally by matrix-isolation infrared spectroscopy) its polymorphic crystalline phases. investigations on allowed us to evaluate major intramolecular interactions determining conformational preferences characterize it in detail from vibrational point view. Two conformers were found (A B), which differ relative orientation ring moieties molecule. Polymorph screening, recrystallization using different solvents, identify three polymorphs, red, orange, yellow colors, subsequently structurally single-crystal X-ray diffraction, vibrationally, Raman spectroscopies (complemented fully periodic differential functional theory calculations crystals), electronically, solid-state ultraviolet–visible absorption spectroscopy, thermodynamically, scanning calorimetry polarized light thermo-microscopy. polymorph be a orange red ones, while last two are packing polymorphs. Mechanistic insights into causes colors polymorphs presented. On whole, reported investigation constitutes comprehensive structural (for phases), spectroscopic, thermal analysis newly prepared compound, with particular emphasis rare polymorphism exhibits.