Skip to main content

Table 1 Computed TD-DFT transitions of indigo in chloroform and experimental data of indigo in solvent, hybrid palygorskite-based Maya blue (Paly-MB) and sepiolite-based Maya blue (Sep-MB)

From: Shades of blue: non-invasive spectroscopic investigations of Maya blue pigments. From laboratory mock-ups to Mesoamerican codices

 TheoreticalExperimental
ChloroformPaly-MBSep-MB
λmax/nm (eV)Compositionλmax/nm (eV)λmax/nm (eV)λmax/nm (eV)
Visible band605 (2.05)H → L (75%)603 (2.06)661 (1.88)642 (1.93)
UV band279 (4.45)H − 1 → L + 1 (87%)286 (4.34)293 (4.23)290 (4.28)