Indigo Molecular Model

A 3D-printable model of indigo (indigotin, PubChem CID: 10215), one of the oldest and most culturally significant organic dyes in human history, universally recognized as the signature pigment of denim blue jeans. This model was exported directly from the open-source web application 3D Printing Molecules, developed through a collaboration between UCT Prague and the 1st Faculty of Medicine, Charles University.

Chemical & Educational Highlights

• Chemical Formula: C16H10N2O2C16H10N2O2

• Molecular Geometry: A symmetric bis-indole core linked via a central double bond (EE-isomer / trans-conformation).

• Chromophore & Color: The extended conjugated ππ-electron system coupled with cross-conjugated electron donor (–NH–) and acceptor (C=O) groups leads to absorption in the yellow-red region, imparting indigo’s deep blue color.

• Intramolecular Hydrogen Bonding: The planar structure is stabilized by intramolecular hydrogen bonds between carbonyl oxygens and amino hydrogens, which is clearly visualized in this space-filling model.

• Industrial Application: A classical water-insoluble vat dye; application to textiles requires chemical reduction into soluble leuco-indigo, followed by fiber fixation and subsequent re-oxidation by atmospheric oxygen.

Model Generation Settings (From Metadata)

• Generator Style: Spheres (van der Waals / CPK space-filling representation)

• Source Dataset: Uploaded 3D conformer (Conformer3D_COMPOUND_CID_10215.sdf)

• Mesh Quality: 50

• Hydrogen Atoms: Included (hydrogens: true)

• Source: Exported directly via 3dmolekuly.vscht.cz