# dmft input variables¶

This document lists and provides the description of the name (keywords) of the dmft input variables to be used in the input file for the abinit executable.

**dmft_charge_prec**¶

*Mnemonics:* Dynamical Mean Field Theory: charge density precision

*Mentioned in topic(s):* topic_DMFT

*Variable type:* real

*Dimensions:* scalar

*Default value:* 1e-06

*Added in version:* before_v9

## Test list (click to open). Rarely used, [2/1027] in all abinit tests, [0/121] in abinit tutorials

Precision to achieve in determining the charge density in the computation of the fermi level. Should be decreased to increase precision. However, for a large system, it can increase importantly computer time.

**dmft_dc**¶

*Mnemonics:* Dynamical Mean Field Theory: Double Counting

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 1

*Added in version:* before_v9

## Test list (click to open). Moderately used, [14/1027] in all abinit tests, [0/121] in abinit tutorials

Value of double counting used for DMFT. Only value 1 is currently activated. It corresponds to the “Full Localized Limit” double counting.

**dmft_entropy**¶

*Mnemonics:* Dynamical Mean Field Theory: ENTROPY

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Only relevant if:* usedmft == 1 and dmft_solv == 5

*Added in version:* before_v9

## Test list (click to open). Rarely used, [3/1027] in all abinit tests, [0/121] in abinit tutorials

If 1, enables the calculation of the entropy within the DMFT framework and so allows one the calculation of the total energy (free energy). In the current implementation, this is only possible with dmft_solv = 5 (Continuous Time Quantum Monte Carlo). See also the input variable dmft_nlambda.

**dmft_iter**¶

*Mnemonics:* Dynamical Mean Field Theory: number of ITERation

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Added in version:* before_v9

## Test list (click to open). Moderately used, [25/1027] in all abinit tests, [0/121] in abinit tutorials

Number of iterations for the DMFT inner loop.

**dmft_kspectral_func**¶

*Mnemonics:* Dynamical Mean Field Theory: compute K-resolved SPECTRAL FUNCtion

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Added in version:* 9.0.0

## Test list (click to open). Rarely used, [0/1027] in all abinit tests, [0/121] in abinit tutorials

When activated, in conjunction with iscf = -2 or -3, a calculation of k-resolved spectral function (or density of state) is possible. However, the calculation requires as input the self-energy computed in the real axis using an external analytical continuation code. The section 7 of the DFT+DMFT tutorial details how to obtain this data and related informations.

**dmft_mxsf**¶

*Mnemonics:* Dynamical Mean Field Theory: MiXing parameter for the SelF energy

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* real

*Dimensions:* scalar

*Default value:* 0.3

*Added in version:* before_v9

## Test list (click to open). Moderately used, [20/1027] in all abinit tests, [0/121] in abinit tutorials

Mixing parameter for the simple mixing of the self-energy (0.3 is safe, but it can be increased most of the time to 0.6).

**dmft_nlambda**¶

*Mnemonics:* Dynamical Mean Field Theory: Number of LAMBDA points

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 6

*Only relevant if:* usedmft == 1 and dmft_entropy == 1

*Added in version:* before_v9

## Test list (click to open). Rarely used, [3/1027] in all abinit tests, [0/121] in abinit tutorials

**dmft_nlambda** gives the number of integration points for the
thermodynamic integration in case of free energy calculation within DMFT.
Its value must be greater or equal to 3.

**dmft_nwli**¶

*Mnemonics:* Dynamical Mean Field Theory: Number of frequency omega (W) in the LInear mesh

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Added in version:* before_v9

## Test list (click to open). Moderately used, [25/1027] in all abinit tests, [0/121] in abinit tutorials

Number of Matsubara frequencies (linear mesh)

**dmft_nwlo**¶

*Mnemonics:* Dynamical Mean Field Theory: Number of frequency omega (W) in the LOg mesh

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Added in version:* before_v9

## Test list (click to open). Moderately used, [25/1027] in all abinit tests, [0/121] in abinit tutorials

Number of frequencies in the log mesh.

**dmft_occnd_imag**¶

*Mnemonics:* Dynamical Mean Field Theory: Occupation non-diagonal imaginary part

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 1

*Added in version:* before_v9

## Test list (click to open). Moderately used, [17/1027] in all abinit tests, [0/121] in abinit tutorials

When 0 force non-diagonal occupations imaginary parts to be null. Do not use this, it is only for compatibility with old tests.

**dmft_rslf**¶

*Mnemonics:* Dynamical Mean Field Theory: Read SeLF energy

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Added in version:* before_v9

## Test list (click to open). Moderately used, [20/1027] in all abinit tests, [0/121] in abinit tutorials

Flag to read/write Self-Energy. If put to one, self-energy is written and read at each DFT iteration. If self-energy file is missing, the self-energy is initialized to the double counting at the first iteration. Importantly, in order to the calculation to restart easily, the self-energy is read and write in the same file.

**dmft_solv**¶

*Mnemonics:* Dynamical Mean Field Theory: choice of SOLVer

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* real

*Dimensions:* scalar

*Default value:* 5

*Added in version:* before_v9

## Test list (click to open). Moderately used, [24/1027] in all abinit tests, [0/121] in abinit tutorials

Choice of solver for the Impurity model.

- 0 → No solver and U=0, J=0 (see upawu and jpawu).
- 1 → DFT+U self-energy is used (for testing purpose)
- 2 → Hubbard one solver in the density density approximation of the Coulomb interaction. The Hubbard one solver is an approximation which gives a rough description of correlated Mott insulators. It should not be used for metals.
- 5 → Use the Continuous Time Quantum Monte Carlo (CTQMC) solver CT-Hyb of ABINIT in the density density approximation of the Coulomb interaction. The calculation is fully parallelised over MPI processes.
- 6 → Continuous Time Quantum Monte Carlo (CTQMC) solver CT-Hyb of TRIQS in the density density representation.
- 7 → Continuous Time Quantum Monte Carlo (CTQMC) solver CT-Hyb of TRIQS with the rotationally invariant formulation.
- 8 → Same as 5, but off-diagonal elements of the hybridization function are taken into account (useful for low symetry systems or with spin orbit coupling).
- 9 → Python invocation. Give a symbolic link to your python interpreter as an input like ‘input-tag’_TRIQS_python_lib and the python script as an input like ‘input-tag’_TRIQS_script.py. The inputs for the script will be written in dft_for_triqs.nc and the output as triqs_for_dft.nc.

The CT Hyb algorithm is described in [Werner2006]. For a discussion of density-density approximation with respect with the rotationnally invariant formulation, see e.g. [Antipov2012]. The ABINIT/CT Hyb implementation is discussed in [Gonze2016]. The TRIQS/CT Hyb implementation is described in [Seth2016]. Before using it, it has to be installed following instructions available here. Until release 8.10 included, the interface was valid only for TRIQS 1.4 and TRIQS/CTHYB 1.4. It has then been upgraded to TRIQS 2.1 afterwards. An example of a config.ac file to compile ABINIT with TRIQS can be found in . See the useful variables for CT-QMC solver: dmftctqmc_basis, dmftctqmc_check, dmftctqmc_correl, dmftctqmc_gmove, dmftctqmc_grnns, dmftctqmc_meas, dmftctqmc_mrka, dmftctqmc_mov, dmftctqmc_order, dmftctqmc_triqs_nleg, dmftqmc_l, dmftqmc_n, dmftqmc_seed, dmftqmc_therm

**dmft_t2g**¶

*Mnemonics:* Dynamical Mean Field Theory: t2g orbitals

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Added in version:* before_v9

## Test list (click to open). Rarely used, [7/1027] in all abinit tests, [0/121] in abinit tutorials

Can be set to 1 only if in cubic symmetry. It enables one to carry a DFT+DMFT
calculations only on *t _{2g}* orbitals.

**dmft_tolfreq**¶

*Mnemonics:* Dynamical Mean Field Theory: TOLerance on DFT correlated electron occupation matrix for the definition of the FREQuency grid

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* real

*Dimensions:* scalar

*Default value:* 0.0001

*Added in version:* before_v9

## Test list (click to open). Rarely used, [3/1027] in all abinit tests, [0/121] in abinit tutorials

- paral: t99.in
- v8: t01.in, t01_triqs2_0.in

The DFT occupation matrix for correlated electrons can be computed directly. It can be compared to the calculation of the same quantity using DFT Green’s function, a sum over Matsubara frequencies and a projection over correlated orbitals. Because the Matsubara grid is finite, the two quantities differ. If this difference is larger than dmft_tolfreq, then the code stops and an error message is given.

**dmft_tollc**¶

*Mnemonics:* Dynamical Mean Field Theory: TOLerance on Local Charge for convergence of the DMFT loop

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* real

*Dimensions:* scalar

*Default value:* 1e-05

*Added in version:* before_v9

## Test list (click to open). Rarely used, [1/1027] in all abinit tests, [0/121] in abinit tutorials

- v6: t45.in

Tolerance for the variation of Local Charge for convergence of the DMFT Loop. Most of the time however, DFT+DMFT calculations can converge fastly using dmft_iter=1, so that this variable is not required.

**dmftbandf**¶

*Mnemonics:* Dynamical Mean Field Theory: BAND: Final

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Added in version:* before_v9

## Test list (click to open). Moderately used, [27/1027] in all abinit tests, [1/121] in abinit tutorials

**dmftbandf** is the last band taken into account in the Projected Local
Orbitals scheme of DFT+DMFT. With dmftbandi, they define the energy window
used to define Wannier Functions (see [Amadon2008]).

**dmftbandi**¶

*Mnemonics:* Dynamical Mean Field Theory: BAND: Initial

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Added in version:* before_v9

## Test list (click to open). Moderately used, [27/1027] in all abinit tests, [1/121] in abinit tutorials

**dmftbandi** is the first band taken into account in the Projected Local
Orbitals scheme of DFT+DMFT. With dmftbandf, they define the energy window
used to define Wannier Functions (see [Amadon2008]).

**dmftcheck**¶

*Mnemonics:* Dynamical Mean Field Theory: CHECKs

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Added in version:* before_v9

## Test list (click to open). Moderately used, [21/1027] in all abinit tests, [0/121] in abinit tutorials

Only for developer purposes.

**dmftctqmc_check**¶

*Mnemonics:* Dynamical Mean Field Theory: Continuous Time Quantum Monte Carlo CHECK

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Only relevant if:* dmft_solv == 5

*Added in version:* before_v9

## Test list (click to open). Rarely used, [4/1027] in all abinit tests, [0/121] in abinit tutorials

Check the fast calculations during the Monte Carlo simulation with very slow but robust methods. Should only be used for debugging.

- 0 → No check.
- 1 → Check the overlap calculations (Impurity operator).
- 2 → Check the update of M matrix calculation (Bath operator).
- 3 → Check both.

**dmftctqmc_correl**¶

*Mnemonics:* Dynamical Mean Field Theory: Continuous Time Quantum Monte Carlo CORRELations

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Only relevant if:* dmft_solv == 5

*Added in version:* before_v9

## Test list (click to open). Rarely used, [4/1027] in all abinit tests, [0/121] in abinit tutorials

Flag to compute statistics about segments and anti-segments during the simulation. Slow down the simulation.

- 0 → Nothing done
- 1 → Calculations performed and written in “Correlation.dat” file

**dmftctqmc_gmove**¶

*Mnemonics:* Dynamical Mean Field Theory: Continuous Time Quantum Monte Carlo Global MOVEs

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Only relevant if:* dmft_solv == 5

*Added in version:* before_v9

## Test list (click to open). Rarely used, [7/1027] in all abinit tests, [0/121] in abinit tutorials

Default is no global moves. The value of this variable is the modulo used to try a global move. A value of 5000 means that a global move is tried every 5000 Monte Carlo sweep.

**dmftctqmc_grnns**¶

*Mnemonics:* Dynamical Mean Field Theory: Continuous Time Quantum Monte Carlo GReeNs NoiSe

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Only relevant if:* dmft_solv == 5

*Added in version:* before_v9

## Test list (click to open). Rarely used, [4/1027] in all abinit tests, [0/121] in abinit tutorials

Compute the statistical noise for each time slice of each green function. This is a good approximation only if there is enough Monte Carlo sweeps per cpu.

- 0 → Nothing
- 1 → Do it and write the noise in the “Gtau.dat” file.

**dmftctqmc_meas**¶

*Mnemonics:* Dynamical Mean Field Theory: Continuous Time Quantum Monte Carlo MEASurements

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 1

*Only relevant if:* dmft_solv == 5

*Added in version:* before_v9

## Test list (click to open). Rarely used, [4/1027] in all abinit tests, [0/121] in abinit tutorials

The modulo used to measure the interaction energy and the number of electrons. Example: 2 means the measure is perform every two sweeps.

**dmftctqmc_mov**¶

*Mnemonics:* Dynamical Mean Field Theory: Continuous Time Quantum Monte Carlo MOVie

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Only relevant if:* dmft_solv == 5

*Added in version:* before_v9

## Test list (click to open). Rarely used, [4/1027] in all abinit tests, [0/121] in abinit tutorials

Print a latex file per cpu displaying the full simulation. This option should only be use with very small number (<1000) of Monte Carlo sweeps since it requires a lot of I/O band width.

- 0 → Nothing
- 1 → Write the “Movie_id.dat” file where id is the MPI rank of each process

**dmftctqmc_mrka**¶

*Mnemonics:* Dynamical Mean Field Theory: Continuous Time Quantum Monte Carlo MARKov Analysis

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Only relevant if:* dmft_solv == 5

*Added in version:* before_v9

## Test list (click to open). Rarely used, [4/1027] in all abinit tests, [0/121] in abinit tutorials

Measure the time evolution of the number of electrons for each orbital and perform a fourier transform. The result can be plotted using the “Markov_id.dat” file

- 0 → Nothing
- 1 → Do it and write the noise in the “Markov_id.dat” file where id is the rank of each MPI process.

**dmftctqmc_order**¶

*Mnemonics:* Dynamical Mean Field Theory: Continuous Time Quantum Monte Carlo perturbation ORDER

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Only relevant if:* dmft_solv == 5

*Added in version:* before_v9

## Test list (click to open). Rarely used, [5/1027] in all abinit tests, [0/121] in abinit tutorials

Print a file containing the statistic distribution of the number of segments
per orbital. The maximal order taken into account **dmftctqmc_order** : 50
means that we have the statistic distribution from 0 to 50 segments. The
result is written in the “Perturbation.dat” file.

**dmftctqmc_triqs_nleg**¶

*Mnemonics:* Dynamical Mean Field Theory: Continuous Time Quantum Monte Carlo perturbation of TRIQS, Number of LEGendre polynomials

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 30

*Only relevant if:* dmft_solv in [6, 7]

*Added in version:* before_v9

## Test list (click to open). Rarely used, [3/1027] in all abinit tests, [0/121] in abinit tutorials

- paral: t99.in
- v8: t01.in, t01_triqs2_0.in

Specify the number of Legendre polynomials used for the calculation of Green’s function in CTQMC code from the library TRIQS. Default is 30. The value of coefficients are given in file whose name ending is “Legendre_coefficient.dat” (see also [Boehnke2011]).

**dmftqmc_l**¶

*Mnemonics:* Dynamical Mean Field Theory: Quantum Monte Carlo time sLices

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 0

*Only relevant if:* dmft_solv >= 5

*Added in version:* before_v9

## Test list (click to open). Moderately used, [13/1027] in all abinit tests, [0/121] in abinit tutorials

Number of time slices used to represent the time green function. This value should be carefully chosen according to Niquist frequency and the tsmear value.

**dmftqmc_n**¶

*Mnemonics:* Dynamical Mean Field Theory: Quantum Monte Carlo Number of sweeps

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* real

*Dimensions:* scalar

*Default value:* 0.0

*Only relevant if:* dmft_solv >= 5

*Added in version:* before_v9

## Test list (click to open). Moderately used, [13/1027] in all abinit tests, [0/121] in abinit tutorials

Number of Monte Carlo sweeps. Should be at least 10^{6<\sup>.}

**dmftqmc_seed**¶

*Mnemonics:* Dynamical Mean Field Theory: Quantum Monte Carlo SEED

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* jdtset

*Only relevant if:* dmft_solv >= 5

*Added in version:* before_v9

## Test list (click to open). Rarely used, [2/1027] in all abinit tests, [0/121] in abinit tutorials

Seed to initialize the random number generator. Should not be relevant except for testing purpose. NOTE: If the CT-QMC (dmft_solv = 5) is used on many CPUs, each CPU initializes its random number generator with dmftqmc_seed+rank where rank is the rank of the cpu in the MPI communicator.

**dmftqmc_therm**¶

*Mnemonics:* Dynamical Mean Field Theory: Quantum Monte Carlo THERMalization

*Characteristics:* DEVELOP

*Mentioned in topic(s):* topic_DMFT

*Variable type:* integer

*Dimensions:* scalar

*Default value:* 1000

*Only relevant if:* dmft_solv == 5

*Added in version:* before_v9

## Test list (click to open). Moderately used, [12/1027] in all abinit tests, [0/121] in abinit tutorials

Number of Monte Carlo sweeps for the thermalization