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Minimalistic structure database for MAPbX3 perovskites: MAPbI3, MAPbBr3 MAPbCl3
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Menno Bokdam - Enschede, the Netherlands
04 June 2021
www.dynamicsolids.net

***The structure database is free to use as long as long as you cite the corresponding paper:***
Bokdam M., Lahnsteiner J., Sarma D.D., J. Phys Chem. C XXXXX (2021)

These structures have been selected with the on-the-fly Machine-Learning Force Fields method:
Jinnouchi R., Lahnsteiner J., Karsai F., Kresse G., Bokdam M., "Phase transitions of hybrid perovskites simulated by machine-learning force fields trained on the fly with Bayesian inference", Phys. Rev. Lett. 122, 225701, (2019)

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Short description
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The structures are selected form a slow heating molecular dynamics run starting out from two possible low temperature orthorhombic structures (sA and sB).

MAPbI3: 110-360 K , heating rate 2/3 K/ps
MAPbBr3: 80-280 K , heating rate 2/3 K/ps
MAPbCl3: 80-280 K , heating rate 2/3 K/ps

Contains the Orthorhombic, Tetragonal and Cubic perovskite phases.

For each 2x2x2 supercell structure the database contains:
* 1 Total potential energy (eV)
* 3 Lattice vectors in Cartesian coordinates (Angstroms)
* 6 Components of the stress tensor (kB)
* 48 atomic position coordinates (x,y,z) in Cartesian coordinates (Angstrom)
* 48 atomic force coordinates (x,y,z) in Cartesian coordinates (eV/Angstrom)

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DFT calculation details
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Applied DFT package:  VASP 6.0 (developers edition)

INCAR:
PREC = FAST
METAGGA = SCAN ; ALGO = Fast
SIGMA = 0.01 ; ISMEAR = 0
ENCUT =  350
NCORE = 5 ; KPAR =4
EDIFF = 1E-4 ; NELMIN = 6
ISYM = 0
LREAL = A
ISIF = 3
MDALGO=3               # use Langevin thermostat
LANGEVIN_GAMMA = 1.0 1.0 1.0 1.0 1.0  # friction coef. for atomic DoFs for each species
LANGEVIN_GAMMA_L=3.0   # friction coef. for the lattice DoFs
PMASS=100              # mass for lattice DoFs
LATTICE_CONSTRAINTS = T T T   # fix x&y, release z lattice dynamics
PSTRESS=0.001          # P is set at 0.001 KB.
POTIM = 2.00
IBRION = 0
SMASS = 0
TEBEG = 110.00D0  # Example for MAPbI3
TEEND = 360.00D0
NSW = 187500
NBLOCK = 5
NWRITE = 1
NELM = 100
ISPIN = 1
INIWAV = 1
IWAVPR = 1
ISTART = 0
LWAVE = .FALSE.
LCHARG = .FALSE.

KPOINTS: 
Automatically(2x2x2->4kpts)
       0
reciprocal
   0.5 0.5 0.0
   -.5 0.5 0.0
   0.0 0.0 0.5
   0.0 0.0 0.0

POTCAR:
   TITEL  = PAW_PBE Pb 08Apr2002
   TITEL  = PAW_PBE I 08Apr2002
   TITEL  = PAW_PBE C_s 06Sep2000
   TITEL  = PAW_PBE N_s 07Sep2000
   TITEL  = PAW_PBE H 15Jun2001

   TITEL  = PAW_PBE Pb 08Apr2002
   TITEL  = PAW_PBE Br 06Sep2000
   TITEL  = PAW_PBE C_s 06Sep2000
   TITEL  = PAW_PBE N_s 07Sep2000
   TITEL  = PAW_PBE H 15Jun2001

   TITEL  = PAW_PBE Pb 08Apr2002
   TITEL  = PAW_PBE Cl 06Sep2000
   TITEL  = PAW_PBE C_s 06Sep2000
   TITEL  = PAW_PBE N_s 07Sep2000
   TITEL  = PAW_PBE H 15Jun2001

