kpath-utilities - SKILL.md Agent Skill

name: kpath-utilities description: K-Path Utilities (5 sub-skills: 1d-kpath, 2d-kpath, bulk-kpath, cp2k-kpath, phonopy-kpath)

K-Path Utilities

Overview

This skill group covers generation of high-symmetry k-point paths for band structure, phonon dispersion, and Wannier90 calculations. It corresponds to VASPKIT menu 03 (tasks 301--309) and provides equivalent functionality using Python tools (seekpath, pymatgen, spglib), with output formatted for Quantum ESPRESSO, VASP, Wannier90, and phonopy.

Sub-Skills

Sub-Skill	Directory	Description
Bulk K-Path	`bulk-kpath/`	Generate k-paths for 3D bulk crystals using seekpath, pymatgen HighSymmKpath, or spglib. Output for QE, VASP, Wannier90, phonopy. Includes BZ visualization. (VASPKIT 301--303)
2D K-Path	`2d-kpath/`	K-paths for 2D materials (hexagonal, square, rectangular lattices). Special handling for 2D Brillouin zones. (VASPKIT 304)
1D K-Path	`1d-kpath/`	K-paths for 1D structures (nanowires, nanotubes). (VASPKIT 305)
Phonopy K-Path	`phonopy-kpath/`	Generate KPATH.in for phonopy, band_conf settings, seekpath integration. (VASPKIT 303, 309)

Method Decision Guide

Need a k-path for a 3D crystal?
  --> bulk-kpath/ (seekpath recommended for standardized paths)

Need a k-path for a 2D material (slab, monolayer)?
  --> 2d-kpath/ (uses 2D BZ conventions)

Need a k-path for a 1D system (nanotube, nanowire)?
  --> 1d-kpath/ (Gamma-X path along the periodic axis)

Need k-path formatted for phonopy?
  --> phonopy-kpath/ (generates band.conf or KPATH.in)

Which k-path convention?
  seekpath (Hinuma et al.)  --> recommended, standardized, handles all 14 Bravais lattices
  pymatgen HighSymmKpath    --> uses Setyawan-Curtarolo convention, well-tested
  spglib                    --> lower-level, useful for custom BZ queries

Common Prerequisites

seekpath: pip install seekpath (recommended for standardized k-paths)
pymatgen: pre-installed (HighSymmKpath, BandStructureSymmLine)
spglib: pre-installed (space group detection, standardization)
matplotlib: pre-installed (BZ visualization)
Structure files: CIF, POSCAR, or pymatgen/ASE Structure objects