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authors: XG
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# Acronyms and other shortenings

Acronym  | Meaning
-------- | -------
BSE      | Bethe-Salpether Equation
cRPA     | constrained Random-Phase Approximation
DDB      | Derivative DataBase
DFPT     | Density Functional Perturbation Theory
DFT      | Density Functional Theory
DFT+U    | Density Functional Theory + U (Hubbard interaction).
DMFT     | Dynamical Mean Field Theory
DOS      | Density Of States
EFG      | Electric Field Gradient
EPH      | Electron-Phonon interaction
FFT      | Fast Fourier Transform
GGA      | Generalized Gradient Approximation
GKK      | (This is not an acronym. Denotes the electron-phonon matrix elements.)  
GW       | (This is not an acronym. G and W stand for 'Green Function' and 'Screened Interaction')
LDA      | Local Density Approximation
LR       | Linear Response
LWF      | Lattice Wannier Function 
MBPT     | Many-Body Perturbation Theory 
MBT      | Many-Body Theory
MD       | Molecular Dynamics
MRG      | Merge (postprocessors like MRGDDB, MRGGKK, ...)
PAW      | Projector-Augmented Waves
PIMD     | Path-Integral Molecular Dynamics
RF       | Response Function
RPA      | Random-Phase Approximation
SCF      | Self-Consistent Field
TD-DFT   | Time-Dependent Density Functional Theory
TDEP     | Temperature Dependence (or Dependent) - also the name of a methodology to deal with anharmonicities.
WF       | Wannier Function  - or sometimes - WaveFunction 
