1. Ab initio calculation on the photoelectron spectrum of methoxide Lan Cheng, Takatoshi Ichino, Marissa Weichman, Jongjin Kim, Dan Neumark, and John Stanton Department of Chemistry, University of Texas at Austin Department of Chemistry, University of California Berkeley

2. CH 3 O Radical 3a 1 2e 1e 2a 1 1a 1 Spatially degenerate open-shell states at C 3v geometry Spin-orbit coupling Subject to moderate Jahn-Teller distortion

3. CH 3 O Radical: Spin-Orbit Coupling Spin-orbit interaction Jahn-Teller effect Spin-orbit interaction constant Displacement coupling state a and state b See, for example, Barckholtz and Miller, Int. Rev. Phys. Chem. 17, 435 (1998).

4. Spin-Vibronic Coupling Spin-orbit interaction lifts the degeneracy “Vibronic quenching” of spin-orbit splitting Spin-orbit splittings for the origin band (in cm -1 ) OHCH 3 OCD 3 O 1396255 The reduction of the spin-orbit splittings serves as a measure of vibronic coupling. Spin Orbit (schematic)

5. Diabatic Spin-Vibronic Model Hamiltonian Köppel-Domcke-Cederbaum (KDC) model Hamiltonian Electronic spin-orbit interaction constant Inter-state coupling constant Schmidt-Kluegmann, Köppel, Schmatz, Botschwina, Chem. Phys. Lett. 369, 21 (2003). Schuurman, Weinberg, Yarkony, J. Chem. Phys. 127, 104309 (2007). Intra-state force constants

6. Ab initio calculations of the parameters in the diabatic Hamiltonian EOMIP-CCSDT/ANO1 linear and quadratic force constants EOMIP-CCSD/ANO0 cubic and quartic force constants The electronic spin-orbit interaction constant for methoxy is computed at EOMIP- CCSD/ANO1 level to be -133 cm -1 at the minimum of the conical intersection seam.

7. Computation on the intensities of the photoelectron spectrum Intensity for the vibronic state Within the Condon-like approximation

8. Vibronic levels: state of CH 3 O Vibronic levelIntensityExperiment 0 0 (E)00.1400 0 0 (E)640.13062 6 1 (A 1 )6830.000682 6 1 (A 2 )9530.000944 3 1 (E)10420.0021043 3 1 (E)11060.0011107 6 1 (E)12340.0641224 6 1 (E)12410.0711232

9. Vibronic levels: state of CH 3 O Vibronic levelIntensityExperiment 5 1 (A 2 )13510.0001344 5 1 (A 1 )14360.0001433 2 1 (E)13570.0231365 2 1 (E)13980.0021413 5 1 (E)15040.0841517 5 1 (E)15100.0451523

10. Photoelectron Spectrum for CH 3 O -

11. 3 1 (E 3/2 ) 3 1 (E 1/2 ) 6 1 (E 1/2 ) 2 1 (E 3/2 ) 2 1 (E 1/2 ) 5 1 (E 3/2 ) 6 2 (E 1/2 ) 6 2 (E 3/2 ) Cheng, Weichman, Kim, Ichino, Neumark, Stanton, to be published. 6 1 (E 3/2 ) 5 1 (E 1/2 )

12. Summary Photoelectron spectrum for CH 3 O - has been computed using a diabatic model Hamiltonian parametrized via ab initio calculations The computational results compare favorably with SEVI experiment