TY - JOUR
T1 - Time-dependent DFT studies of metal core-electron excitations in Mn complexes
AU - Jaszewski, Adrian R.
AU - Stranger, Rob
AU - Pace, Ronald J.
PY - 2008/11/6
Y1 - 2008/11/6
N2 - Time-dependent density functional theory (TDDFT) has been applied to study core excitations from Is and 2p Mn orbitais in a series of manganese complexes with oxygen and nitrogen donor ligands. The effect of basis set and functional on the excitation energy was evaluated in detail for one complex, Mn(acac) 2·(H2O)2. The results obtained for a range of compounds, namely, [Mn(Im)6]Cl2, Mn(CHsCOO) 2· 4H2O, Mn(acac)3, Mn(SALADHP) 2 and [Mn(SALPN)O]2, show good consistency with the data from X-ray absorption spectroscopy (XAS), confirming the relation between the Mn K-edge energy and the oxidation state of the Mn atom. The energies predicted for 2p core excitations show a dependence on the metal oxidation state very similar to that determined experimentally by ls2p resonant inelastic X-ray scattering (RIXS) studies for Mn(acac)2·(H2O) 2, Mn(acac)3, and Mn(sal)2(bipy). The reliability of the K-edge energies obtained in the present study indicates that TDDFT can be used in determining the oxidation states of Mn atoms in different computational models of the manganese cluster of photosystem II (PSII).
AB - Time-dependent density functional theory (TDDFT) has been applied to study core excitations from Is and 2p Mn orbitais in a series of manganese complexes with oxygen and nitrogen donor ligands. The effect of basis set and functional on the excitation energy was evaluated in detail for one complex, Mn(acac) 2·(H2O)2. The results obtained for a range of compounds, namely, [Mn(Im)6]Cl2, Mn(CHsCOO) 2· 4H2O, Mn(acac)3, Mn(SALADHP) 2 and [Mn(SALPN)O]2, show good consistency with the data from X-ray absorption spectroscopy (XAS), confirming the relation between the Mn K-edge energy and the oxidation state of the Mn atom. The energies predicted for 2p core excitations show a dependence on the metal oxidation state very similar to that determined experimentally by ls2p resonant inelastic X-ray scattering (RIXS) studies for Mn(acac)2·(H2O) 2, Mn(acac)3, and Mn(sal)2(bipy). The reliability of the K-edge energies obtained in the present study indicates that TDDFT can be used in determining the oxidation states of Mn atoms in different computational models of the manganese cluster of photosystem II (PSII).
UR - http://www.scopus.com/inward/record.url?scp=56349108493&partnerID=8YFLogxK
U2 - 10.1021/jp803286c
DO - 10.1021/jp803286c
M3 - Article
SN - 1089-5639
VL - 112
SP - 11223
EP - 11234
JO - Journal of Physical Chemistry A
JF - Journal of Physical Chemistry A
IS - 44
ER -