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Fapbi3 Cif File [WORKING]

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Fapbi3 Cif File [WORKING]

data_FAPbI3_alpha
_symmetry_space_group_name_H-M 'P m -3 m'
_cell_length_a 6.362
_cell_length_b 6.362
_cell_length_c 6.362
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Pb Pb 0.00000 0.00000 0.00000
I I 0.00000 0.50000 0.50000
C C 0.50000 0.50000 0.50000
N N 0.34200 0.50000 0.50000
N N 0.65800 0.50000 0.50000
H H 0.44000 0.50000 0.50000
... (remaining hydrogen atoms)

For a solid feature in a FAPbI3 (Formamidinium Lead Iodide) CIF file, the

structure is the most critical for high-efficiency solar applications. 1. Key Structural Parameters (

The cubic phase is characterized by its high symmetry and corner-sharing octahedra. A standard CIF for this phase typically includes these parameters: Space Group (No. 221). Lattice Constant ( : Approximately Cell Angles Crystal System 2. Common CIF Data Entry

Below is a representative snippet of the atom site coordinates for a perfectly cubic cap F cap A cap P b cap I sub 3

structure at room temperature. Note that in refined CIFs, the organic cap F cap A raised to the positive power cation (Formamidinium) is often modeled as disordered due to its rapid rotation within the lead-iodide cage. Site Occupancy Source: Adapted from GitHub - WMD-group/hybrid-perovskites 3. Stability Considerations is the goal for performance, cap F cap A cap P b cap I sub 3

is metastable at room temperature and tends to transition to the (hexagonal, yellow, non-perovskite). ResearchGate FAPbI3.cif - WMD-group/hybrid-perovskites - GitHub

#====================================================================== # CRYSTAL DATA #------------------------------------------

Understanding FAPbI₃: The Power of the CIF File in Perovskite Research

In the rapidly evolving world of solar energy research, FAPbI₃ (Formamidinium Lead Iodide) has emerged as a frontrunner. As scientists push the boundaries of perovskite solar cells (PSCs), the ability to understand and manipulate the material's atomic arrangement is crucial. This is where the CIF (Crystallographic Information File) becomes an indispensable tool. What is FAPbI₃?

FAPbI₃ is an organic-inorganic hybrid perovskite. Compared to its predecessor, MAPbI₃ (Methylammonium Lead Iodide), it offers a narrower bandgap (approx. 1.48 eV), which is closer to the ideal Shockley-Queisser limit for single-junction solar cells. This makes it theoretically capable of achieving higher power conversion efficiencies.

However, FAPbI₃ is famous for its phase instability. At room temperature, it tends to transition from the photoactive -phase (black, cubic) to the non-photoactive

-phase (yellow, hexagonal). Understanding this transition starts with the crystal structure. What is a CIF File?

A CIF file (.cif) is the standard format for exchanging crystallographic data. It contains everything needed to reconstruct the 3D lattice of a material, including: Unit cell dimensions (a, b, c) and angles ( Space group symmetry (e.g., Pm3m for cubic FAPbI₃). fapbi3 cif file

Atomic coordinates (x, y, z positions for Formamidinium, Lead, and Iodide). Occupancy and thermal parameters.

For researchers, the CIF file is the "blueprint" used in software like VESTA, Diamond, or Mercury to visualize the crystal and perform DFT (Density Functional Theory) simulations. Key Phases of FAPbI₃ and Their Crystallographic Data

When searching for an FAPbI₃ CIF file, you are likely looking for one of two primary polymorphs: 1. The Alpha Phase ( -FAPbI₃) Symmetry: Cubic (Pm3m) or slightly distorted Tetragonal.

Characteristics: This is the "black phase" desired for solar cells. It features a high-symmetry corner-sharing PbI6cap P b cap I sub 6 octahedral network with the FA⁺ cation in the center.

CIF Utility: Used for simulating light absorption, charge transport, and band structure. 2. The Delta Phase ( -FAPbI₃) Symmetry: Hexagonal (P6₃mc).

Characteristics: The "yellow phase." It consists of face-sharing octahedra, which traps charges and prevents efficient solar energy conversion.

CIF Utility: Essential for researchers studying phase stabilization and how to prevent the degradation of solar panels. Why the FAPbI₃ CIF File is Essential for Research A. Theoretical Modeling (DFT)

Computational chemists use CIF files as the starting point for Density Functional Theory calculations. By importing the FAPbI₃ coordinates, they can predict how adding "additives" (like Cesium or Methylammonium) might stabilize the black phase. B. X-Ray Diffraction (XRD) Analysis

Experimentalists use CIF files to generate reference XRD patterns. When a lab synthesizes a new batch of FAPbI₃, they compare their experimental peaks against the pattern derived from the CIF file to confirm they have successfully created the C. Structural Engineering

Visualizing the CIF file allows researchers to see the "tilt" of the PbI6cap P b cap I sub 6

octahedra. Subtle changes in these angles—often induced by temperature or pressure—drastically affect the material's electronic properties. Where to Find FAPbI₃ CIF Files

If you are looking to download these files for your own research, the most reliable repositories include: For a solid feature in a FAPbI3 (Formamidinium

Crystallography Open Database (COD): A massive open-access collection of crystal structures.

The Cambridge Structural Database (CSD): Ideal for organic-inorganic hybrids like FAPbI₃.

Materials Project: Provides computed CIF files along with predicted electronic properties.

Published Literature: Most high-impact papers in journals like Nature Energy or JACS include CIF data in their Supporting Information. Conclusion

The FAPbI₃ CIF file is more than just data; it is the foundational map for the next generation of solar technology. Whether you are a computational physicist or a lab-based materials scientist, mastering the structural nuances contained within these files is the key to unlocking stable, high-efficiency perovskite energy.

A Crystallographic Information Framework (CIF) file for FAPbI₃ (Formamidinium Lead Iodide) contains the essential structural data—such as lattice parameters, space groups, and atomic coordinates—needed to model this solar cell material in software like VESTA or Materials Project. Key Phases and Their Structural Parameters

FAPbI₃ is polymorphic, meaning it exists in different crystal structures depending on temperature and stability conditions. Common Name Crystal System Space Group Lattice Constant ( -phase Black Perovskite ≈6.36is approximately equal to 6.36

>150∘is greater than 150 raised to the composed with power -phase Black Perovskite Tetragonal Intermediate -phase Yellow Non-Perovskite P63mccap P 6 sub 3 m c Stable at room temp Critical Information in the CIF A-Site Cation: The formamidinium ion is organic and planar. In the -phase, it is orientationally disordered within the octahedral cages.

Inorganic Framework: The framework consists of corner-sharing lead iodide octahedra. The bond lengths are typically around Phase Transition: The "yellow"

-phase is the most common room-temperature form, but it is not photoactive for solar cells. Research often focuses on stabilizing the "black" -perovskite phase. Where to Find FAPbI₃ CIFs

You can download verified structural files from these major databases:

Materials Project: Provides computed and experimental data for the cubic and hexagonal phases. Once you have fapbi3.cif

Crystallography Open Database (COD): Contains experimental CIFs derived from published X-ray diffraction (XRD) studies.

GitHub Repository (WMD-group): Hosts specific refined CIF files for hybrid perovskites, including "perfect" cubic models for computational use.

How to run DFT calculations on lower-end PCs? (Free and Fast)

Title: Structural Elucidation and Symmetry-Composition Relations in Formamidinium Lead Triiodide (FAPbI$_3$): A Deep Dive into the $Fm\bar3m$ to $Pm\bar3m$ Transition via Powder Diffraction Analysis

Abstract

Formamidinium lead triiodide (HC(NH$_2$)$_2$PbI$_3$ or FAPbI$_3$) represents the forefront of next-generation photovoltaic materials, offering a reduced bandgap closer to the Shockley-Queisser optimum compared to its methylammonium counterpart. However, the structural instability of the photoactive perovskite phase ($\alpha$-phase) remains a critical bottleneck. This paper provides a comprehensive crystallographic analysis of the FAPbI$_3$ Crystallographic Information File (CIF), focusing on the temperature-dependent phase transitions from the cubic $Fm\bar3m$ (or pseudo-cubic $Pm\bar3m$) structure to the non-perovskite hexagonal $P6_3mc$ phase. Through simulated Rietveld refinement and group-subgroup analysis, we deconvolute the orientational disorder of the formamidinium cation and its impact on the lattice parameters, offering a definitive guide for interpreting experimental diffraction data.

In the rapidly evolving field of photovoltaics, Formamidinium Lead Iodide (FAPbI₃) has emerged as the frontrunner material for next-generation perovskite solar cells (PSCs). With a bandgap of approximately 1.48 eV and superior thermal stability compared to its methylammonium (MA) counterpart, FAPbI₃ is now the gold standard for achieving power conversion efficiencies (PCEs) exceeding 25%.

However, any serious computational study—whether it involves Density Functional Theory (DFT), molecular dynamics (MD), or geometric optimization—starts with a single, critical file: the CIF (Crystallographic Information Framework) file.

But finding a reliable, phase-accurate fapbi3.cif file is surprisingly non-trivial. Why? Because FAPbI₃ exists in multiple polymorphs (primarily cubic α-phase and hexagonal δ-phase), and its structure is highly sensitive to temperature and lattice strain.

This article provides a comprehensive overview of what the FAPbI₃ CIF file contains, where to find it, how to validate it, and how to use it in common software like VESTA, Quantum ESPRESSO, and VASP.

Once you have fapbi3.cif, you must check for errors. Bad CIFs lead to non-physical DFT energies.

FAPbI₃ (formamidinium lead iodide) is a hybrid organic-inorganic perovskite with the chemical formula HC(NH₂)₂PbI₃. It is a promising light-absorbing material in high-efficiency perovskite solar cells (PSCs) due to its optimal band gap (~1.48 eV) and excellent thermal stability compared to its methylammonium counterpart (MAPbI₃).