Fig. 1: Overview of the chemical system and the ATAS results.
a Schematic of the orbital structure of \({{{{{{\rm{SiH}}}}}^{+}_{4}}}\) and its fragments. The energetic ordering, occupation and symmetry of the orbitals of \({{{{{{\rm{SiH}}}}}^{+}_{4}}}\) and its fragments in various relevant geometries is shown. The SFI pump process is represented with a yellow arrow while the XAS (probe) transitions are represented by purple lines. Solid lines indicate the dominant observed transitions. b The results of an ATAS measurement on silane, whose measured static absorption is plotted in the top panel. The core-valence (102–104.5 eV) and core-Rydberg (104.5–107.5 eV) transitions of SiH4 are clearly separated, with the latter showing far narrower features. The blueshift of the L2,3-absorption edge of the cationic species (shown as a blue arrow) is discussed in Supplementary Section S2.2.
