Official Resources
- Homepage: https://bruceravel.github.io/demeter/
- GitHub: https://github.com/bruceravel/demeter
- Documentation: https://bruceravel.github.io/demeter/documents/
- Publication: B. Ravel, M. Newville, J. Synchrotron Rad. 12, 537 (2005)
- License: Artistic License 2.0
Overview
Demeter is a comprehensive software package for processing and analyzing X-ray Absorption Spectroscopy (XAS) data. It includes three main programs: Athena (data processing), Artemis (EXAFS fitting with FEFF), and Hephaestus (periodic table and X-ray data). Built on the IFEFFIT library, Demeter provides a complete workflow for XAS analysis.
Scientific domain: X-ray absorption spectroscopy, XANES, EXAFS
Target user community: XAS researchers and synchrotron beamline users
Theoretical Methods
- XANES data processing
- EXAFS Fourier transform analysis
- FEFF path-based fitting
- Multiple scattering theory
- Linear combination fitting
- Principal component analysis
Capabilities (CRITICAL)
- Athena: Data import, calibration, alignment, merging, normalization
- Artemis: EXAFS fitting with FEFF paths, multiple dataset fitting
- Hephaestus: X-ray data lookup, absorption calculations
- Multi-platform: Windows, macOS, Linux
- FEFF Integration: Built-in FEFF6 support
- Batch Processing: Project-based workflow
Sources: Demeter documentation, J. Synchrotron Rad. publication
Key Strengths
Complete Workflow:
- Data import to final fit
- Athena + Artemis integration
- Project management
- Reproducible analysis
User-Friendly:
- GUI-based interface
- Interactive plotting
- Extensive documentation
- Tutorial materials
FEFF Integration:
- Built-in FEFF6
- Path generation
- Multiple scattering
- Fitting interface
Inputs & Outputs
-
Input formats:
- ASCII column data
- Athena project files
- Multiple beamline formats
- CIF files for FEFF
-
Output data types:
- Athena project files (.prj)
- Artemis project files
- Fit reports
- Publication-ready figures
Installation
# Download from GitHub releases
# Windows installer available
# macOS and Linux: build from source or use package managers
Usage Examples
# Athena workflow:
1. Import data files
2. Calibrate energy scale
3. Align and merge scans
4. Set normalization parameters
5. Export for Artemis fitting
# Artemis workflow:
1. Import Athena data
2. Run FEFF calculation from CIF
3. Build fitting model with paths
4. Perform fit and analyze results
Performance Characteristics
- Speed: Efficient IFEFFIT backend
- Memory: Handles typical XAS datasets
- Stability: Production-ready software
Limitations & Known Constraints
- Perl-based: Older codebase compared to Larch
- GUI-focused: Less scriptable than Larch
- FEFF6 only: Built-in FEFF is version 6
- Development: Transitioning to Larch
Comparison with Other Tools
- vs Larch: Demeter GUI-focused, Larch Python-native
- vs FEFF: Demeter analysis, FEFF calculation engine
- vs standalone codes: Demeter comprehensive workflow
- Unique strength: Complete GUI workflow, extensive documentation
Application Areas
- Synchrotron XAS experiments
- Catalysis and materials science
- Environmental chemistry
- Coordination chemistry
- Bioinorganic chemistry
Best Practices
- Use reference compounds for calibration
- Document all processing parameters
- Validate fits with multiple approaches
- Save projects for reproducibility
Community and Support
- GitHub repository
- XAFS mailing list
- Extensive documentation
- Bruce Ravel (developer)
Verification & Sources
Primary sources:
- Homepage: https://bruceravel.github.io/demeter/
- B. Ravel, M. Newville, J. Synchrotron Rad. 12, 537 (2005)
- GitHub: https://github.com/bruceravel/demeter
Confidence: VERIFIED - Published in J. Synchrotron Rad.
Verification status: ✅ VERIFIED
- Official homepage: ACCESSIBLE
- Documentation: COMPREHENSIVE
- Source code: OPEN (GitHub)
- Academic citations: >3000
- Active development: Maintained