• Developed a Grand Canonical Monte Carlo (GCMC) 2D perovskite crystal growth simulation code in Python programming language, employing the machine-learned potential, leveraging PyLammps library as an interface to LAMMPS molecular simulation package for energy evaluations of the supercell structures during the trial moves;
• Trained the machine-learning enabled potential for butylammonium (BA) based 2D perovskite material employing the Behler-Parrinello feed-forward neural network (FFNN) method based on the Gaussian descriptor as implemented in Atomistic Machine-learning Package (AMP);
• Assembled a training set from ab-initio molecular dynamics trajectories (AIMD) including the most important inter-atomic contributions in 2D perovskite material as an input for the subsequent machine learning of the artificial neural network (ANN) force-field;
• Carried out the surface structure of low-index facets in 2D Ruddlesden-Popper material from density functional theory (DFT) calculations,
- extracted surface features revealed that low surface energies stem from hydrogen bond shortening increasing the strength of Coulomb interaction between organic cations and iodine atom;
# results presented at the WCCM ECCOMAS Conference in Paris, France (01-2021);
• DFT study of adsorption of small organic molecule on lead-free antimony-based all-inorganic perovskite,
- calculations revealed noticeably stronger affinity of O atom within the N-methylpyrrolidone (NMP) molecule to Cs atom in all-inorganic Cs3Sb2I9 perovskite compared to S atom within thiourea (TU) leading to better morphology and increased stability of the active layer of the solar cell device;
• Carried out large scale DFT study of intertwined defect in 2D layered Ruddlesden-Popper 2D perovskite material in VASP,
- extracted the band structure and density of states (DOS) of the resulting trajectories reveal shallow defects and Fermi level pinning features in the material;
* all calculations carried out on Taiwania I, II and III supercomputers;
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@ Computational Nanomaterials & Nanomechanics Lab