Lasttime1. Explicit solvation models2. Implicit solvation models2
Last time 2 1. Explicit solvation models 2. Implicit solvation models
ContentsExcitedstates1. Absorption and emission model2. Methods for excited states3. Excited state geometry4. SolvatochromismCramer,Chp14ForesmanandFrisch,Chp9
Contents 3 Excited states 1. Absorption and emission model 2. Methods for excited states 3. Excited state geometry 4. Solvatochromism Cramer, Chp 14 Foresman and Frisch, Chp 9
Ground stateand excited state configurations=...2=.·N/2double excitationground statesingly excited configurations
Ground state and excited state configurations ground state singly excited configurations double excitation 4
VerticalabsorptionandemissionElectronicExcitationofx-x-Excited StateexcitedstateGround StateA=absorptionF=fluorescenceEgroundsQuinineAbsorptionandEmissionSpectraWavelength(Nanometers)300350400600450500100StokesFigure444ShiftEmissionEadiabatic80Absorptionaao6040S+S,20S+S2S+SGeneric coordinatehttp://gaussian.com/freg/33.32.812.412.00Wavenumber(cmx10-3)Option,VibronicSpectra:Franck-Condon,Herzberg-TellerandFCHT
Vertical absorption and emission 5 http://gaussian.com/freq/ Option, Vibronic Spectra: Franck-Condon, Herzberg-Teller and FCHT
KoopmanstheoremOrbital energyofan occupied orbital is approximatelyequal to the minus of the ionization potential of thatorbital;IP of Φ, = -S;Can be derived from the Hartree-Fock energy expression,if one assumes that the orbitals do not relax afterionization;In a similar spirit, one can approximate the excitationenergy;E(a)-E(Y)= 8-8,E(Yab)-E(Y)=8. +&, -&, -8)6
Koopmans theorem • Orbital energy of an occupied orbital is approximately equal to the minus of the ionization potential of that orbital; IP of fi = -ei ; • Can be derived from the Hartree-Fock energy expression, if one assumes that the orbitals do not relax after ionization; • In a similar spirit, one can approximate the excitation energy; a b i j ab i j a i a i E E E E e e e e e e − = + − − − = − ( ) ( ) ( ) ( ) 0 0 6