TY - JOUR
T1 - Theoretical Evidence of Solvent-Mediated Excited-State Dynamics in a Functionalized Iron Sensitizer
AU - Pápai, Mátyás Imre
AU - Abedi, Mostafa
AU - Levi, Gianluca
AU - Biasin, Elisa
AU - Nielsen, Martin Meedom
AU - Møller, Klaus Braagaard
PY - 2019
Y1 - 2019
N2 - The solvent-mediatedexcited-state dynamics of the COOH-functionalized Fe-carbene photosensitizer [Fe(bmicp)2]2+ (bmicp= 2,6-bis(3-methyl-imidazole-1-ylidine)-4-carboxy-pyridine) is studied by time-dependent density functional theory, as well as classical and quantum dynamics simulations. We demonstrate the crucial role of the polar acetonitrile solvent in stabilizing the metal-to-ligand charge transfer (MLCT) states of the investigated molecule using the conductor polarizable continuum model. This leads to dynamics that avoid sub-ps back electron transfer to the metal and an exceptionally long-lived 1MLCT state that does not undergo sub-ps 1MLCT → 3MLCT intersystem crossing as it is energetically isolated. We identify two components of the excited-state solvent reorganization process: an initial rotation (∼300 fs) and diffusional dynamics within the local cage surrounding the rotated solvent molecule (∼2 ps). Finally, it is found that the relaxation of the solvent only slightly affects the excited-state population dynamics of [Fe(bmicp)2]2+.
AB - The solvent-mediatedexcited-state dynamics of the COOH-functionalized Fe-carbene photosensitizer [Fe(bmicp)2]2+ (bmicp= 2,6-bis(3-methyl-imidazole-1-ylidine)-4-carboxy-pyridine) is studied by time-dependent density functional theory, as well as classical and quantum dynamics simulations. We demonstrate the crucial role of the polar acetonitrile solvent in stabilizing the metal-to-ligand charge transfer (MLCT) states of the investigated molecule using the conductor polarizable continuum model. This leads to dynamics that avoid sub-ps back electron transfer to the metal and an exceptionally long-lived 1MLCT state that does not undergo sub-ps 1MLCT → 3MLCT intersystem crossing as it is energetically isolated. We identify two components of the excited-state solvent reorganization process: an initial rotation (∼300 fs) and diffusional dynamics within the local cage surrounding the rotated solvent molecule (∼2 ps). Finally, it is found that the relaxation of the solvent only slightly affects the excited-state population dynamics of [Fe(bmicp)2]2+.
U2 - 10.1021/acs.jpcc.8b10768
DO - 10.1021/acs.jpcc.8b10768
M3 - Journal article
SN - 1932-7447
VL - 123
SP - 2056
EP - 2065
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
IS - 4
ER -