Yambo Input Flags Reference

This document provides a comprehensive reference for all input flags and command-line options available in Yambo/Yambo. The flags are organized by category for easy navigation.

Table of Contents

1. Command-Line Options
2. Self-Energy Calculations
3. Initializations
4. Response Functions
5. Bethe-Salpeter Equation
6. Total Energy
7. Real-Time Dynamics
8. Hamiltonians & Potentials
9. Control Options
10. Run Levels
11. Basic Parameters
12. K-Points and Grids
13. Temperature and Occupation
14. Parallel Execution
15. Input/Output Control
16. Self-Energy and GW Calculations
17. Response Functions (X)
18. Bethe-Salpeter Equation (BSE)
19. BSE Solvers
20. TDDFT and Exchange-Correlation
21. Dipoles
22. Coulomb Interaction and RIM
23. Cutoff Techniques
24. ACFDT
25. Advanced Options

Command-Line Options

Yambo/Yambo calculations are initiated using command-line options that specify the calculation type and parameters. These options can be combined to perform complex calculations.

Self-Energy Calculations

Example:

yambo -p c -g n -x    # COHSEX calculation with Newton solver and HF
yambo -p p -g g       # GW with plasmon-pole and Green's function solver

Initializations

Example:

yambo -i              # Generate input file
yambo -r              # Setup Coulomb potential with RIM

Response Functions

Example:

yambo -o c -k hartree    # Chi calculation with Hartree kernel
yambo -o b -k sex        # BSE calculation with screened exchange kernel
yambo -d -k alda         # Response function with ALDA kernel

Bethe-Salpeter Equation

Example:

yambo -o b -y h       # BSE with Haydock solver
yambo -o b -y d       # BSE with full diagonalization

Total Energy

Example:

yambo --acfdt         # ACFDT calculation

Real-Time Dynamics

Example:

yambo_rt -n p -s ee      # Real-time with pump field and e-e scattering
yambo_rt -n pp -s ee+ep  # Pump-probe with e-e and e-ph scattering
yambo_nl -u n            # Non-linear optics

Hamiltonians & Potentials

Example:

yambo_sc -s -v hf        # Self-consistent Hartree-Fock
yambo_sc -s -v sex       # Self-consistent screened exchange
yambo_rt -v ip -e        # Real-time with IP potential and collisions

Control Options

Example:

yambo -F input.in -V qp      # Use input.in with QP verbosity
yambo -i -V all              # Generate input with all variables
yambo -J "GW_calc" -O outdir # Set job name and output directory

Run Levels

Run levels determine which calculation type to perform. These are typically set via command-line options (see above) and appear in the input file.

Basic Parameters

Fundamental parameters that control the basic setup of the calculation.

K-Points and Grids

Parameters controlling k-point sampling and grid selection.

Temperature and Occupation

Parameters related to electronic and bosonic temperatures and occupation.

Parallel Execution

Parameters controlling parallel execution and threading.

OpenMP Threading (if compiled with OpenMP):

Input/Output Control

Flags controlling file I/O and database management.

Self-Energy and GW Calculations

Parameters for GW and self-energy calculations.

Band and Component Selection

Damping and Energy Parameters

Solvers and Sampling

Green's Function Parameters

Terminator

Flags

Self-Consistent Calculations

Response Functions (X)

Parameters for calculating the response function (polarizability).

Mode and Algorithm

Terminator

Q-vector Parameters

Database and Output

Flags

Bethe-Salpeter Equation (BSE)

Parameters for BSE kernel construction and electron-hole interaction.

Mode and Kernel

Bands and Energy Windows

G-vectors Components

Q-points

Kernel Cutoff and I/O

Gauge and Properties

Flags

BSE Solvers

Parameters for solving the BSE and computing optical spectra.

Solver Selection

Energy Grid and Damping

Field Directions

Haydock Solver

Diagonalization Solver

Inversion Solver

Additional Parameters

Flags

TDDFT and Exchange-Correlation

Parameters for TDDFT kernels and exchange-correlation functionals.

Kernel Parameters

LRC (Long-Range Corrected) Parameters

PF (Parameter-Free) Parameters

Memory and Precision

Flags

Dipoles

Parameters for dipole matrix element calculations.

Flags

Coulomb Interaction and RIM

Parameters for the Coulomb interaction and Random Integration Method.

RIM (Random Integration Method)

Environment

Flags

Cutoff Techniques

Parameters for Coulomb cutoff in reduced dimensionality systems.

Flags

ACFDT

Parameters for ACFDT (Adiabatic Connection Fluctuation-Dissipation Theorem) calculations.

Advanced Options

Photoluminescence

Testing and Debugging

System Setup

Units

Yambo/Yambo uses the following unit conventions:

• Energy: Hartree (Ha), Rydberg (Ry), or eV depending on input
• Temperature: Kelvin (K)
• Length: Bohr radius (a.u.)
• Time: Atomic units (ℏ/Ha)
• G-vectors: Reciprocal lattice units

Units can be specified in the input file. Common unit specifications: - Energy: eV, Ha, Ry, meV - Temperature: K - Time: fs, as

Input File Format

Input files in Yambo/Yambo follow this general format:

# Comments start with #

ParameterName = value [unit]

# For ranges
ParameterRange = value1 | value2 [unit]

# For vectors
VectorParameter = value1 | value2 | value3

# For flags (boolean)
%FlagName

Example Input File

# GW calculation example

# Run level
gw0                              # GW approximation

# Bands and k-points
GbndRnge = 1 | 100               # Bands range
IkSigLim = 1 | 10                # K-points range

# G-vectors
EXXRLvcs = 2 Ry                  # Exchange RL components
CORRLvcs = 2 Ry                  # Correlation RL components

# Energy grid
GEnSteps = 2                     # Energy steps
GEnRnge = -10.0 | 10.0 eV        # Energy range

# Solver
DysSolver = "n"                  # Newton solver

# Parallel
X_Threads = 4                    # OpenMP threads

See Also

• Yambo Official Documentation
• Yambo Tutorials
• Yambo Forum

Notes

1. Flag vs Parameter: Flags (marked with % in input files) are boolean switches that don't take values. Parameters require values.

2. Conditional Compilation: Some flags are only available if Yambo/Yambo was compiled with specific options (e.g., _ELPH, _RT, _NL, _SC, _QED).

3. Default Values: Many parameters have sensible defaults. Only specify parameters you need to change.

4. Case Sensitivity: Parameter names are case-sensitive. Flag names in string parameters (like solver names) may have specific case requirements.

5. Verbosity Levels: Many parameters have associated verbosity levels that control how much information is printed during execution.

This documentation was automatically generated from the INIT_load.F source file. Last updated: 2025