Input Parameters

This document provides a comprehensive list of input parameters for the MuST code. It includes default values, allowed ranges, and technical logic extracted from the source input files.

Each parameter is defined in the main input file (typically start with i_, for example, i_mst) using the format:

Key :: Value

General Execution & File I/O

Key	Default Value	Options / Notes
Current File Path	./	—
Output to Screen (y/n)	n	y or n
Output Level (>= -1)	0	Must be ≥ -1
Output Proc. ID (>= -1)	0	-1: All processors write to individual output files; ≥ 0: logical processor indices (space/comma separated) that write to unit 6
Output Atom ID (>= -1)	0	-1: Output all atoms in unit cell; 0: Output atoms mapped to output processor; ≥ 1: global atom indices (space/comma separated)

SCF Calculations

Key	Default Value	Options / Notes
No. Iterations (> 0)	60	Must be > 0
Method of SCF Calculation	2	1: LSMS; 2: KKR; 3: KKR-CPA
No. Gauss Pts. along r	80	—
No. Gauss Pts. along theta	60	—
Valence Band Bottom Est.	-0.5	—
Temperature Parameter (K)	0.000	—
DOS Run ID	0	0: DOS along real energy axis will not be calculated; >0: integer representing global atom index for DOS calculation; -1: DOS calculated for all atoms
Ewald parameter for KKR	0.5d0	Only needed in KKR/KKR-CPA calculations

Tolerance Parameters

Key	Default Value	Options / Notes
Energy (Ryd) Tol (> 0)	0.000001	Must be > 0
Potential Tol (> 0)	0.0000001	Must be > 0
Fermi Energy Tol (> 0)	0.0000001	Must be > 0
Other RMS Tol (> 0)	0.0000001	Must be > 0
Tolerance for setting up polyhedra	0.0000005d0	Note: Adjust if errors occur when determining corners/edges of polyhedra
Negative charge density tolerance	0.00001	Note: If -tol < rho(r) < 0, set rho(r) = 0

System

Key	Default Value	Options / Notes
No. Atoms in System (> 0)	1	Must be > 0
Atomic Position File Name	position.dat	—
Text Identification	D	—
Alloy System Description	D, Default structure	—
Default Radical Plane Ratio	1.000	Note: Ratio of radical plane distance relative to universal value applied to system

Full-potential Method Parameters

Key	Default Value	Options / Notes
Single Site Solver (>= 0)	2	0: Spherical Schrodinger; 1: Spherical Dirac; 2: Full Schrodinger; 3: Full Dirac
Single Site Solution Method (>= -1)	2	-1: Untruncated potential in solver, surface integration; 0: Untruncated potential in solver, Untruncated potential in volume integration; 1: Untruncated potential in solver, Truncated potential in volume integration; 2: Truncated potential in solver. Note: Defines how site potential is used in the iterative coupled integral solver; truncated potential is enforced if irregular solutions are used; default = 0
Irregular Solutions (>=0)	1	0: Solver does NOT use the Irregular Solutions; 1: Solver does use the Irregular Solutions
Pole Search Step (>0.0)	0.010	Note: Defaults to 0.01 for unspecified value; valid range <=0.0 or >0.4
Bound State Contour Integration Radius (>0.0)	0.001	Note: Radius of the semi-circle contour around the bound state energy for density integration
Resonance State Max Width (>0.0)	0.050	Note: If a pole in 4th quadrant has distance from real axis < this value, considered as a resonance; imaginary part is width
Resonance State Contour Integration Radius (>0.0)	0.002	Note: Radius of semi-circle contour around resonance energy if its width < this value
No. Gauss Pts. along Resonance State Contour	5	Note: Number of Gaussian quadrature points for integration along semi-circle contour around resonance energy
No. Gauss Pts. along Bound State Contour	5	Note: Number of Gaussian quadrature points for integration along semi-circle contour around bound energy
Solutions Lmax Cutoff	-1	l<0: uses lmax of wave functions in info_table; l≥0: coupled integral solver used up to this l, beyond it only radial solutions used
Compute Phase Shifts (>=0)	0	0: Does not print phase shifts; 1: generates phase shifts and stops code
SS Lmax Potential Solver	-1	Note: Defines potential lmax in single site solver; if <0, defaults to info_table lmax; otherwise minimum of this lmax and potential lmax is used
Uniform Grid Parameters	64 64 64	>0: Three integers defining grid numbers along Bravais lattice vectors; must be powers of 2; affects Poisson solver accuracy
Default Lmax-Wave Func	4	Note: Expansion of solutions of Schrödinger equation; internally computed if <0, otherwise takes specified value ≥ Lmax_T
Default Lmax-Potential	8	Note: Expansion of LDA potential used in SCF (0 ≤ Lmax-Pot ≤ 2*Lmax-T)
Default Lmax-Trunc Pot	12	—
Default Lmax-Charge Den	8	Note: Expansion of charge density (0 ≤ Lmax-Charge ≤ 2*Lmax-T)
Default Pseudo Charge Radius	0.9	Note: Ratio of pseudo charge radius to muffin-tin radius
Uniform Grid Origin	0	0: unit cell corner; 1: unit cell center
Uniform Grid Origin Vector	0.0 0.0 0.0	—
Full-potential Semi-core	0	0: do NOT treat semi-core with full-potential; 1: treat semi-core with full-potential

Electronic Structure & Potential

Key	Default Value	Options / Notes
Val. Electron Rel (>= 0)	0	0: Non-relativistic; 1: Scalar-relativistic; 2: Full-relativistic
Charge Symmetry (>=0)	1	0: No symmetry imposed; 1: Symmetry imposed from spherical scattering calculation
Potential Type (>= 0)	0	0: Muffin-tin; 1: ASA; 2: Muffin-tin ASA; 3: Full; 4: Muffin-Tin Test; 5: Empty Lattice; 6: Mathieu Potential
Exch-Corr. LDA Type (>= 0)	0	0: Barth-Hedin; 1: Vosk-Wilk-Nusair; 2: Perdew-Zunger; 3: Perdew-Wang GGA; 4: PBE Note: Can also use LibXC-style functional names like LDA_X+LDA_C_HL or GGA_X_PBE+GGA_C_PBE

Spin and Magnetic-Moment Parameters

Key	Default Value	Options / Notes
Moment Direction File Name	Evec_input.dat	Require only for spin-canted case
Spin Index Param (>= 1)	1	1: No Spin; 2: Spin-polarized; 3: Spin-canted
Interstitial Electron Spin	1	1: No Spin; 2: Spin-polarized
Default Moment Direction	0.00 0.00 1.00	—
Default Constrain Field	0.00 0.00 0.00	—

Energy Contour Parameters

Key	Default Value	Options / Notes
Read E-mesh from emeshs.inp	0	0: No; 1: Yes. If yes, following parameters for energy contour have no effect
Contour Type (>= 0)	0	0: Semi-circle; 1: Rectangle Box; 2: Horizontal Line; 3: Vertical Line
Number of Contours (> 0)	1	Must be > 0
Energy Grid Type (>= 0)	1	0: Equal Interval; 1: Gaussian Points; 2: Log Interval; 3: Nicholson Points
No. Energy Grids	30	—
No. Extra Energy Points	5	—
Offset Energy Point	0	—
Real Axis Bottom, erbot	-0.40	—
Real Axis Top, ertop	0.00	—
Imag Axis Bottom, eibot	0.001	—
Imag Axis Top, eitop	1.000	—
Iterate Fermi energy	0	0: Off; 1: On
SS Real Axis Int. Method	0	0: Unimesh; 1: Adaptive; 2: Uniform; 3: Gaussian Quadrature; 4: Romberg Method
SS Real Axis Int. Points	300	—
Imaginary energy shift	0.001	Note: If -tol < rho(r) < 0, set rho(r) = 0 (DOS calculation)

SCF Mixing Schemes and Parameters

Key	Default Value	Options / Notes
Mixing quantity type	1	0: Charge mixing; 1: Potential mixing
Mixing algorithm	2	0: Simple mixing; 1: DGA mixing; 2: Broyden mixing
Lloyd correction	0	0: Off; 1: On
Lloyd mode	1	1: first method (to be defined by Markus); 2: second method (to be defined by Markus)
Default Rho Mix Param.	0.1000	—
Default Pot Mix Param.	0.1000	—
Default Mom Mix Param.	0.1500	—
Default Chg Mix Param.	1.0000	—
Default Evec Mix Param.	0.0000	—
Default Mixing Parameter	0.1000	Note: Default value for mixing
Mixing Parameter for Finding Ef	0.5	Note: New Fermi energy = mixing of calculated and old Fermi energies at each SCF step
Mixing Switch for Finding Ef	0.01	Note: If difference > switch value, mixing is applied; 0 disables Fermi energy mixing

Kpoint Parameters (Required only for KKR and KKR-CPA)

Key	Default Value	Options / Notes
K-space Solver Method	0	0: SuperLU; 1: SuperLU with direct solve checking; 2: Direct (1 CPU only)
Read K-mesh from kmeshs.inp	0	0: No; 1: Yes. If yes, following parameters for k-points generation have no effect
Scheme to Generate K (>=0)	0	0: Special K-points; 1: Tetrahedron; 2: Direction
No. K Meshs in IBZ (> 0)	1	Note: Number of sets of k-points, not total k-points
Kx, Ky, Kz Division (> 0)	16 16 16	—
Symmetrize BZ Integration	1	0: No; 1: Yes; 2: Yes (Equivalent points)

Potential and LMAX Parameters

Key	Default Value	Options / Notes
Large sphere radius (a.u.)	1000.0	—
Default Potential Input File Name	D_fp_v	—
Default Potential Input File Form	1	0: ASCII Format; 1: XDR Format; 2: HDF Format; 3: Machine Dependent Binary
Default Potential Output File Name	D_fp_w	—
Default Potential Output File Form	1	0: ASCII Format; 1: XDR Format; 2: HDF Format; 3: Machine Dependent Binary
Default Lmax-T matrix	4	Note: Controls KKR size
Default Lmax-Step Func	16	Note: Step function expansion used for volume integration in single site solver (0 ≤ Lmax-Step < Infinity)

Local Interaction Zone (LIZ) Parameters (Required only for LSMS)

Key	Default Value	Options / Notes
Default LIZ # Neighbors	350	Note: Maximum number of neighbors of a site; actual number may be less if the next shell exceeds maximum
Default LIZ # NN Shells	16	—
Default LIZ Shell Lmax	4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4	—
Default LIZ Cutoff Radius	25.0	—

Radial Grid Parameters

Key	Default Value	Options / Notes
Default No. Rad Points ndivin	1001	0: Not specified; >0: Specified. Note: 0 < r(j)=exp(j*hin) ≤ rmt, j=1,2,…,ndivin
Default No. Rad Points ndivout	0	0: Not specified; >0: Specified. Note: rmt < r(j)=exp(j*hout) ≤ rmax, j=1,2,…,ndivout
Default Integer Factor nmult	1	0: Not specified; >0: Specified. Note: r(j)=exp(j*hin), hin = nmult*hout
Default Radial Grid Exponential Step	0.01	0.0: Not specified; >0.0: recommended 0.005–0.02. Note: r(j)=exp(j*hin), hin = exponential step
Default Muffin-tin Radius	0	0: inscribed sphere radius; 1: implicit muffin-tin radius; >0: specific value in a.u.

Core States Solver Parameters

Key	Default Value	Options / Notes
Frozen-Core Calculation	0	Note: 0: Not a frozen core calculation; >0: SCF iteration beyond which frozen core applies
Frozen-Core File Name	‘ ‘	Note: File to read if a frozen-core file name is given
Core Electron Rel (>= 0)	0	0: Non-relativistic; 1: Full-relativistic
Default Maximum Core Radius	0.0d0	—
Default Core Radius	0	-1: circumscribed sphere radius; 0: inscribed sphere / muffin-tin / ASA radius; 1: implicit core radius; >0: specific value in a.u.
Core States Normalization Range	0	0: up to bounding sphere radius; 1: up to infinity

Effective Medium Parameters

Key	Default Value	Options / Notes
Maximum Effective Medium Iterations	40	Note: 0 → ATA (instead of CPA) calculation will be performed
Effective Medium Mixing Scheme	2	0: Simple mixing; 1: Anderson mixing; 2: Broyden mixing; 3: Anderson Mixing by Messina group
Effective Medium Mixing Parameters	0.1000 0.01	Note: First value = energy points in standard mixing; second value = energy points in conservative mode
Effective Medium Mixing eSwitch Value	0.003	Note: If Re[E] > 0 and Im[E] < eSwitch, iteration switches to conservative mode
Number of iterations with aggressive mixing	25	Note: Number of CPA iterations per aggressive mixing scheme
Maximum number of mixing scheme changes	10	Note: Maximum number of mixing scheme changes
Effective Medium T-matrix Tol (>0)	0.0000001	—
Include CPA/SRO Charge Correction	0	0: do NOT include correction; 1: include correction term in potential/energy for CPA
Use Linear Relation	0	0: do NOT use linear q-V relation; 1: use linear q-V relation for charge correction

MPI-GPU Parameters

Key	Default Value	Options / Notes
Maximum MPI tasks per GPU for KKR Matrix Inverse	28	Note: If the number of MPI tasks exceeds this, GPU acceleration of KKR matrix inverse is disabled
Maximum MPI tasks per GPU for KKR Matrix Calculation	4	Note: If MPI tasks exceed this, KKR matrix is calculated on CPU and copied to GPU for inversion
Maximum MPI tasks per GPU for Gij Matrix Calculation	4	Note: If MPI tasks exceed this, Gij matrix is calculated on CPU and copied to GPU for inversion

Under development Methods

Spin Dynamics Parameters

Canted Moment Torque Coef.	0.0	—
Calculate J_ij (y/n)	n	y or n
No. Spin-dynamics Time Steps (>= 0)	1	—
Spin-dynamics Time Step	1.000	—

Screened KKR Parameters

SuperLU Tol (> 0)	0.0000001	Must be > 0
K-space Check Tol (> 0)	0.0000001	Must be > 0
Default Screen Pot.	3.0	Note: Default value of the screened potential
Default Lmax-Screen	3	Note: Maximum angular momentum for screening
Default Rcut-Screen	4.8	Note: Cutoff radius for screening (a.u.)

DFT+DMFT Parameters

Key	Default Value	Options / Notes
Perform DFT+DMFT Calculation	0	0: No; 1: Yes
Default Local Orbital Labels	d	Note: Allowed values are s, p, d, f, separated by ‘ ‘(space), ‘,’(comma), or ‘;’(semicolon)
Default Local s-Orbital Energy	0.2	Note: Real value in Rydberg units
Default Local p-Orbital Energy	0.3	Note: Real value in Rydberg units
Default Local d-Orbital Energy	0.5	Note: Real value in Rydberg units
Default Local f-Orbital Energy	0.4	Note: Real value in Rydberg units
Default Local Orbital Energy	0.5	Note: Real value in Rydberg units
Initial Fermi Energy Setting	0	0: Set to average of Fermi energy from input potential 1: Set to average of Max and Min of Fermi energy from input potential >0: User-specified real number as initial Fermi energy

Beyond DFT

Key	Default Value	Options / Notes
Calculate Superconducting Tc	0	0: No (Default); 1: Yes
mu* (e-e interaction constant)	0	0: Bennemann and Garland formula (Default); 0,A: Modified BG formula with factor A (<1.0)
Average of phonon frequency (1/sec)	0.0	Note: Input format is a real positive value
Average of phonon frequency (K)	0.0	Note: Input format is a real positive value
Average of phonon frequency squared (1/sec^2)	0.0	Note: Input format: atomic index or chemical element symbol, followed by a real positive value
Average of phonon frequency squared (K^2)	0.0	Note: Input format: atomic index or chemical element symbol, followed by a real positive value
Atomic mass times <omega^2> (eV/Anst^2)	0.0	Note: Input format: atomic index or chemical element symbol, followed by a real positive value
Atomic mass times <omega^2> (Ryd/BohrRad^2)	0.0	Note: Input format: atomic index or chemical element symbol, followed by a real positive value
Debye Temperature (K)	0	0: get from internal database; >0: user-provided real positive value
LDA Improvement Scheme	0	0: No improvement; 1: LDA + U; 2: LDA + SIC; 3: LDA + DFMT
LDA+U Parameter File Name	UJ.dat	Note: If name is ‘None’, data will be obtained by other methods
Local SIC	0	Note: 0: Off; 1: On (local self-interaction correction)

Visualization Parameters

Generate System Movie	0	0: No system movie output (default); 1: generate movie
Stop-at Routine Name	main	—
No. Iter for Each Pot. Write	5	—
No. Iter for Each Movie	0	0: No system movie output (default); ≥ 1: a system movie is written at the end of every this number of SCF iterations
Visual Grid Type (0<D<4)	3	1: Define a line (1D); 2: Define a plane (2D); 3: Define a rectilinear region (3D)
Visual Grid Scale	1.00	—
Visual Grid Origin Vector	0.0 0.0 0.0	—
Visual Grid Vector 1	10.00 0.00 0.00	Note: Vector defining grid boundaries
Visual Grid Vector 2	0.00 10.00 0.00	Note: Vector defining grid boundaries
Visual Grid Vector 3	0.00 0.00 10.00	Note: Vector defining grid boundaries
Visual Grid Points	10 10 10	Note: Only first D parameters are used for Grid Vectors and Grid Points
Visual Line Vector	1.00 0.00 0.00	—
Visual Line Points	10	—
Output Electron Density ID (>= -1)	-1	-1: do not print; 0: print brief data; 1: print data on visual grid
Output Density Format	2	0: x y z rho format; 1: Legacy “.vtk” format for ParaView; 2: “.xsf” format for VESTA

Under development Parameters

Calc. Harris Energy (H.E.)	0	0: Do not calculate H.E.; 1: H.E. at Updated μ; 2: H.E. at Fixed μ
Additional Electrons	0.0	Note: Additional number of electrons in a unit cell; can be <, =, or > 0; mainly for testing; default = 0
T-matrix inversion (>= 0)	2	—
M-matrix inversion (>= 0)	10	0: LU method; 2: QMR method
Renormalize Green function	0	0: do NOT renormalize; 1: renormalize using integrated DOS from Lloyd/Krein formula

Atomic Position File (position.dat)

The position.dat file defines the structural framework and chemical composition of the system.

Structure Definition

• Lattice Constant: The first line defines the global scaling factor (e.g., 5.53).

• Bravais Vectors: Three lines defining the primitive lattice vectors.

• Site Position: Cartesian coordinates (x, y, z) for each atom in the cell.

Crystal Structure: CuZn (BCC)

5.53
# Bravais lattice
    1.00000000000    0.00000000000    0.0000000000
    0.00000000000    1.00000000000    0.0000000000
    0.00000000000    0.00000000000    1.0000000000
# Atomic position
Cu  0.00000000000    0.00000000000    0.00000000000
Zn  0.50000000000    0.50000000000    0.50000000000

Crystal Structure: Cu-Zn Random Alloy (FCC, CPA)

5.53
# Bravais lattice
     0.50000000000    0.50000000000   -0.50000000000
     0.50000000000   -0.50000000000    0.50000000000
    -0.50000000000    0.50000000000    0.50000000000
# Atomic position
CPA  0.00000000000    0.00000000000    0.00000000000  Cu  0.50000  Zn  0.50000

Notes

• For random alloy calculations, use ‘CPA’ as the virtual atom name.

• Coordinates are Cartesian (x, y, z) of the virtual atom.

• The atomic species and their site concentrations follow the coordinates.