Official Resources
- Homepage: https://www.cohp.de/
- Documentation: http://www.cohp.de/
- Source Repository: Part of LOBSTER or other implementations
- License: Varies (LOBSTER is academic free)
Overview
Status: METHOD/TOOL - COHP refers to the Crystal Orbital Hamilton Population method, a theoretical framework for analyzing chemical bonding in solids by partitioning the band structure energy into bonding and antibonding contributions. While "COHP" is a method, the term is often used to refer to the LOBSTER code (which implements it) or legacy codes like Cray-COHP.
Scientific domain: Chemical bonding analysis, solid-state chemistry
Target user community: Solid-state chemists, materials scientists
Theoretical Methods
- Partitioning of band structure energy
- Bonding/Antibonding analysis
- Projected density of states (pDOS)
- Crystal Orbital Overlap Population (COOP)
- Integrated COHP (ICOHP) for bond strength
Capabilities (CRITICAL)
- Visualization of bonding interactions (bonding vs. antibonding)
- Quantitative assessment of bond strengths (ICOHP)
- Analysis of electronic stability
- Implemented in: LOBSTER (standard), tight-binding codes, some DFT packages (SIESTA, LMTO)
Sources: Dronskowski and Bloechl, J. Phys. Chem. 97, 8617 (1993)
Key Strengths
Chemical Insight:
- Direct bonding/antibonding visualization
- Energy-resolved analysis
- Quantitative ICOHP values
- Intuitive interpretation
Solid-State Focus:
- Designed for crystals
- Periodic boundary support
- Band structure connection
- Extended systems
Wide Implementation:
- LOBSTER (primary)
- SIESTA/LMTO codes
- Academic standard
- Well-documented theory
Inputs & Outputs
- Input: Wavefunctions/Hamiltonians from DFT (VASP, QE, etc.)
- Output: COHP vs Energy plots, ICOHP values
Interfaces & Ecosystem
- LOBSTER: The main modern implementation
- LobsterPy: Python analysis tool
- VASP/QE: Source of electronic structure data
Limitations & Known Constraints
- Projection dependent: Results depend on local basis choice
- Not unique: Different projections give different COHP
- Interpretation: Requires chemical knowledge
- Implementation: Mainly via LOBSTER for plane-wave codes
Comparison with Other Tools
- vs COOP: COHP energy-weighted, COOP overlap-weighted
- vs Bader: COHP bonding analysis, Bader charge partitioning
- vs ELF: Different perspectives on bonding
- Unique strength: Direct bonding/antibonding energy analysis
Application Areas
- Phase stability analysis
- Magnetic ordering origins
- Bond strength in intermetallics
- Surface adsorption
Best Practices
- Use adequate k-point sampling
- Choose appropriate energy window
- Compare ICOHP values for bond strength ranking
- Validate with known compounds
Verification & Sources
Primary sources:
- Homepage: https://www.cohp.de/
- Publication: R. Dronskowski, P. E. Bloechl, J. Phys. Chem. 97, 8617 (1993)
Confidence: VERIFIED
Verification status: ✅ VERIFIED
- Method: STANDARD
- Implementation: Primarily via LOBSTER
- Applications: Bonding analysis