High-order harmonic generation (HHG) in aligned linear molecules can offer valuable information about strong-field interactions in lower-lying molecular orbitals, but extracting this information is difficult for three-dimensional molecular geometries
. Our measurements of the asymmetric top SO2 show large axis dependencies, which change with harmonic order. The analysis shows that these spectral features must be due to field ionization and recombination from multiple orbitals during HHG. We expect that HHG can probe orbital dependencies using this approach for a broad class of asymmetric-top molecules.
