Figure 4
From: Fully fluorinated non-carbon compounds NF3 and SF6 as ideal technosignature gases
The molecular spectra phalanx plot compares the absorbance spectra amongst molecules. The x axis is wavenumber ranging from 4000 to 500 cm−1 (2.5–20 μm). The y axis is the order of the molecules. Color represents the intensity of the absorption peaks; yellow and green represent strong absorption, while blue and purple represent weak or no absorption. Note the absorbance is normalized to 1. The spectra phalanx provides a visualization of which molecules are clustered together in wavelength based on their spectral data. Functional groups are labeled at their clustering points. The grey dashed lines near the top of the plot mark NF3 and SF6 and show their relative uniqueness in wavenumber space as compared to other halogenated species. The spectra data are from 600 gas species in our All Small Molecules Database (ASM)40 (volatile molecules with up to 6 non-H atoms) that have available spectra in NIST64. See “Methods” for details on construction of this figure.
