FIG. 8.

Acetylacetone. Carbon K-edge NEXAFS from the T₁($\pi {\pi }^{\ast }$) (a) and S₂($\pi {\pi }^{\ast }$) (b) states. The spectra of T₁($\pi {\pi }^{\ast }$) were computed at the potential energy minimum of T₁($\pi {\pi }^{\ast }$). The spectra of S₂($\pi {\pi }^{\ast }$) were computed at the potential energy minimum of S₁(n${\pi }^{\ast }$). Blue: CVS-EOM-CCSD. Red: LSOR-CCSD. Magenta: HSOR-CCSD. Green: Ground-state spectrum at the FC geometry. (c), (d) Black: Experimental transient absorption spectra at the delay times of 7–10 ps and 120–200 fs,²² respectively. Red: computational transient absorption spectra made from the red and the green curves of (a) and (b), respectively, shifted by −0.9 eV as the spectrum of the ground state [see panel (b) of Fig. 5]. The red curves of panels (a) and (b) were scaled by 0.75 and from these, the green ground-state spectrum, scaled by 0.25, was subtracted. FWHM of the Lorentzian convolution function is 0.4 eV for panels (a) and (b), 0.6 eV for panels (c) and (d), respectively. Basis set: 6-311++G^**.