KPROJ

KPROJ is a program for unfolding electronic and phononic band structures of materials modeled by supercells. It enables visualization of effective primitive cell band structures from supercell calculations, essential for studying defects…

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Overview

KPROJ is a program for unfolding electronic and phononic band structures of materials modeled by supercells. It enables visualization of effective primitive cell band structures from supercell calculations, essential for studying defects, alloys, and interfaces.

Reference Papers

Reference papers are not yet linked for this code.

Full Documentation

Official Resources

  • Homepage: https://arxiv.org/abs/2410.10910
  • Documentation: arXiv:2410.10910
  • License: Open Source

Overview

KPROJ is a program for unfolding electronic and phononic band structures of materials modeled by supercells. It enables visualization of effective primitive cell band structures from supercell calculations, essential for studying defects, alloys, and interfaces.

Scientific domain: Band unfolding, supercell calculations, phonon dispersions
Target user community: Researchers working with supercell calculations

Theoretical Methods

  • Band structure unfolding
  • Spectral weight calculation
  • Supercell to primitive cell mapping
  • k-point projection
  • Phonon unfolding
  • Electronic unfolding

Capabilities (CRITICAL)

  • Electronic band unfolding
  • Phonon band unfolding
  • Supercell calculations
  • Layer projection
  • Twisted bilayer support
  • DFT code interfaces
  • Spectral function output

Key Strengths

Dual Unfolding:

  • Both electronic and phononic
  • Unified framework
  • Consistent methodology
  • Versatile application

Supercell Support:

  • Defect calculations
  • Alloy studies
  • Interface systems
  • Twisted structures

Inputs & Outputs

  • Input formats:

    • DFT output files
    • Phonon eigenvectors
    • Supercell information
  • Output data types:

    • Unfolded band structures
    • Spectral weights
    • Effective dispersions

Interfaces & Ecosystem

  • VASP: Primary interface
  • Phonopy: Phonon input
  • Python: Analysis tools

Advanced Features

  • Dual unfolding: Both electronic and phononic band structures
  • Layer projection: Layer-resolved spectral weights
  • Twisted bilayer support: Moiré superlattice calculations
  • Spectral weight calculation: Bloch character analysis
  • Multiple DFT codes: VASP and Phonopy interfaces

Performance Characteristics

  • Post-processing tool: Fast
  • Scales with supercell size
  • Python-based implementation

Computational Cost

  • Supercell DFT/phonon calculation: External (dominant cost)
  • KPROJ unfolding: Fast (minutes)
  • Overall: Minimal overhead for unfolding

Best Practices

  • Use commensurate supercell-primitive mapping
  • Check spectral weight convergence
  • Validate against primitive cell bands when possible
  • Use appropriate broadening for visualization

Limitations & Known Constraints

  • Recent development
  • Limited documentation
  • Specific DFT codes
  • Expert-level tool

Application Areas

  • Defect phonons
  • Alloy band structures
  • Interface studies
  • Twisted bilayers
  • Disordered systems

Verification & Sources

Primary sources:

  1. arXiv: https://arxiv.org/abs/2410.10910

Confidence: VERIFIED

Verification status: ✅ VERIFIED

  • Published methodology
  • arXiv preprint

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