Tuning the solid-state color properties of pigments tailored for specific applications is extremely important. With the aim of designing new organic pigment materials, binary and ternary solid-state forms of the natural plant pigment quercetin (Qur) were synthesized with two dipyridine derivatives 4,4′-ethylenedipyridine (BPA) and 4,4′-azobispyridine (AP) based on the supramolecular synthon approach. The obtained two cocrystals and four cocrystal solvates were identified and characterized thoroughly with powder and single-crystal X-ray diffractions as well as thermal analysis containing thermogravimetric analysis, differential scanning calorimetry, and hot-stage microscopy. Similar lattice parameters, molecular conformations, packing patterns, and intermolecular interactions revealed that the binary cocrystals Qur−BPA and Qur−AP are isostructural. Meanwhile, the robust porous structure framework composed of tetramers and the volume of solvent molecules play a critical role in the formation of isostructural ternary cocrystal solvates (Qur−AP−acetone and Qur−AP−dioxane). The quantitative similarity parameters via CrystalCMP and XPac programs further proved the corresponding isostructurality. These obtained solid-state forms of Qur exhibit colors ranging from pale-yellow, earthy yellow, orange, to dark red. An explanation for the observed different colors of the multicomponent crystals was rationalized using a combination of UV−vis absorption spectra and density functional theory calculations as well as π−π stacking interactions. Finally, the accelerated stability experiments were conducted and the results show that Qur−AP presents better stability than Qur−BPA, which can offer promising development value for new organic pigments.

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