Jablonski Diagram

electronic ground state

A F

P

en

erg

y

IC

ISC

IC

S0

S1

S2

Sn

(ro)-vibrationalstates of el. excited states

T1

T2

A = photon absorptionF = fluorescenceP = phosphorescenceS = singlet stateT = triplet stateIC = internal conversionISC = inter-system crossing

Typical “Mirror Image” Behavior of Fluorescence and Absorption

(From P. Atkins et al.”Physical Chemistry”)

(From A. Zewail’s Nobel Lecture 1999)

From: Yves Jean “Molecular Orbitals of Transition Metal Complexes”

-bonds in transition metal complexes

From: Yves Jean “Molecular Orbitals of Transition Metal Complexes”

Interactions of the d-block in transition metal complexes

From: Yves Jean “Molecular Orbitals of Transition Metal Complexes”

Interactions of the d-block in transition metal complexes

From: Yves Jean “Molecular Orbitals of Transition Metal Complexes”

Interactions of the d-block in octahedral transition metal complexes (Oh)

depends on - and -interactions

d-d transitions are Laporte-forbidden (both are gerade orbitals)

From: Yves Jean “Molecular Orbitals of Transition Metal Complexes”

Interactions of the d-block in transition metal complexesSquare-planar complexes (D4h)

From: Yves Jean “Molecular Orbitals of Transition Metal Complexes”

Interactions of the d-block in transition metal complexesTetrahedral complexes (Td)

Crystal and Solution Spectra of Permanganate

aq. solution, 100 M

KMnO4 in KClO4 @ 4 K

J. Houmøller et al., CPC 13 (2013) 1133

Permanganate

1T2• Jahn-Teller distortion in excited states (C3v, C2v, D2d)• extensive vibronic coupling in 2T2 and 3T2 states• calculated excitation energies problematic• assignments of transitions strongly debated until recently (Nooijen 2005, Ziegler 2011/2012)

From G. Herzberg, Molecular Spectra and Molecular Structure,

Vol. III