4 Other Computational Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
4.1 Density Functionals for Core Excitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
4.2 Expansion of the Polarizability in Electron–Hole Operators . . . . . . . . . . . . . . . . . . . . . . . . 324
4.3 Double Excitations and the X-Ray Double-Quantum-Coherence Signal . . . . . . . . . . . 328
4.4 Ionization, Photoelectron Signals and Resonances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
4.5 Vibronic Coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
5 Conclusions and Perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 336
Abbreviations
ADC
Algebraic diagrammatic construction
AES
Auger electron spectroscopy
AIMD
ab initio molecular dynamics
ASRS
Attosecond stimulated Raman spectroscopy
BO
Bohn–Oppenheimer
CAP
Complex absorption potential
CASPT2
Complete active space second-order perturbation theory
CASSCF
Complete active space self-consistent field
CASSI
Complete active space state interaction
CC
Coupled cluster
CCSD
Coupled cluster singles and doubles
CEO
Collective electronic oscillator
CFM
Crystal field multiplet
CI
Configuration interaction
CIS
Configuration interaction singles
CoIn
Conical intersection
CPP
Complex polarization propagator
CSF
Configuration state function
CV
Core-valence
CV-DFT
Constricted variational density functional theory
DCH
Double core hole
DFT
Density functional theory
DMRG
Density matrix renormalization group
DQC
Double-quantum-coherence
ECH
Equivalent core hole
EET
Excitation energy transfer
EOM
Equation of motion
ET
Electron transfer
EXAFS
Extended X-ray absorption fine structure
FC
Frank–Condon
FCH
Full core hole
FORS
Full optimization reaction space
GGA
Generalized gradient approximation
GSB
Ground state bleaching
274
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4.1 Density Functionals for Core Excitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
4.2 Expansion of the Polarizability in Electron–Hole Operators . . . . . . . . . . . . . . . . . . . . . . . . 324
4.3 Double Excitations and the X-Ray Double-Quantum-Coherence Signal . . . . . . . . . . . 328
4.4 Ionization, Photoelectron Signals and Resonances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
4.5 Vibronic Coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
5 Conclusions and Perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 336
Abbreviations
ADC
Algebraic diagrammatic construction
AES
Auger electron spectroscopy
AIMD
ab initio molecular dynamics
ASRS
Attosecond stimulated Raman spectroscopy
BO
Bohn–Oppenheimer
CAP
Complex absorption potential
CASPT2
Complete active space second-order perturbation theory
CASSCF
Complete active space self-consistent field
CASSI
Complete active space state interaction
CC
Coupled cluster
CCSD
Coupled cluster singles and doubles
CEO
Collective electronic oscillator
CFM
Crystal field multiplet
CI
Configuration interaction
CIS
Configuration interaction singles
CoIn
Conical intersection
CPP
Complex polarization propagator
CSF
Configuration state function
CV
Core-valence
CV-DFT
Constricted variational density functional theory
DCH
Double core hole
DFT
Density functional theory
DMRG
Density matrix renormalization group
DQC
Double-quantum-coherence
ECH
Equivalent core hole
EET
Excitation energy transfer
EOM
Equation of motion
ET
Electron transfer
EXAFS
Extended X-ray absorption fine structure
FC
Frank–Condon
FCH
Full core hole
FORS
Full optimization reaction space
GGA
Generalized gradient approximation
GSB
Ground state bleaching
274
Y. Zhang et al.