title: Electronic and Molecular Structure of the Transient Radical Photocatalyst Mn(CO)5 and Its Parent Compound Mn2(CO)10.
abstract: We present a time-resolved X-ray spectroscopic study of the structural and electronic rearrangements of the photocatalyst Mn2(CO)10 upon photocleavage of the metal-metal bond. Our study of the manganese K-edge fine structure reveals details of both the molecular structure and valence charge distribution of the photodissociated radical product. Transient X-ray absorption spectra of the formation of the Mn(CO)5 radical demonstrate surprisingly small structural modifications between the parent molecule and the resulting two identical manganese monomers. Small modifications of the local valence charge distribution are decisive for the catalytic activity of the radical product. The spectral changes reflect altered hybridization of metal-3d, metal-4p, and ligand-2p orbitals, particularly loss of interligand interaction, accompanied by the necessary spin transition due to radical formation. The spectral changes in the manganese pre- and main-edge region are well-reproduced by time-dependent density functional theory and ab initio multiple scattering calculations.
authors.affiliation: Department of Chemistry and Chemistry Institute of Functional Materials, Pusan National University , Busan 46241, Republic of Korea.|Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
authors.forename: Hana
authors.initials: H
authors.lastname: Cho
authors.affiliation: Department of Chemistry and Chemistry Institute of Functional Materials, Pusan National University , Busan 46241, Republic of Korea.|Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
authors.forename: Kiryong
authors.initials: K
authors.lastname: Hong
authors.affiliation: Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Strader
authors.affiliation: Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
authors.forename: Jae Hyuk
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Ultrafast X-ray Science Laboratory, Chemical Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Schoenlein
authors.affiliation: Department of Physics, University of Hamburg, Max Planck Institute for the Structure and Dynamics of Matter, and Center for Free-Electron Laser Science , 22761 Hamburg, Germany.
authors.forename: Nils
authors.initials: N
authors.lastname: Huse
authors.affiliation: Department of Chemistry and Chemistry Institute of Functional Materials, Pusan National University , Busan 46241, Republic of Korea.
authors.forename: Tae Kyu
authors.initials: TK
authors.lastname: Kim