Fig. 7. Analysis of the oxygen K-edge TRXAS signatures for malonaldehyde along the non-radiative decay pathway of two initial conditions. (a–c) IC1 and (d–f) IC2. (a and d) Time evolution of key geometric parameters and adiabatic state populations. Line color indicates the adiabatic state while the transparency is proportional to the squared amplitude of the given TBF. (b and e) TRXAS contributions from IC1 that decays directly to S1via the HTI seam and remains trapped near the S1 minimum, and from IC2 that evolves to the twisted intersection seam and deactivates via S1 to the ground state. The colormap shows the NEXAFS cross section (in a.u.). The oscillatory changes during the first ∼40 fs in (e) follow the evolution in the BLA and H-transfer (HT) parameters, where HT = RO1H4 − RO2H4. (c and f) NEXAFS spectra of S0 and S2, respectively, at the initial geometry. Insets at the top show the centroids of the TBFs representing the AIMS nuclear wavepacket on a given adiabatic state. The stick spectra were only convolved in the energy domain with a Gaussian line shape function (FWHM: 1.0 eV). Spectra were computed at the ADC(2)/CVS-ADC(2)-x level using the 6-31+G* basis set and have been shifted −2.625 eV (cf. Fig. S3†).
