Laboratory X-ray Absorption Spectroscopy on Empyrean

High-quality XANES and EXAFS Across a Broad Elemental Range

X-ray Absorption Spectroscopy (XAS) is a powerful element-specific technique for probing oxidation states, electronic structure, and local atomic environments. XANES (X-ray Absorption Near Edge Structure) provides information on oxidation state and coordination geometry, while EXAFS (Extended X-ray Absorption Fine Structure) reveals local atomic structure, including interatomic distances and coordination numbers.

Traditionally, routine XAS measurements have relied on synchrotron facilities, where access can be limited by availability and scheduling constraints. The Empyrean platform brings XAS into the laboratory, enabling direct access to high-quality XANES and EXAFS measurements for both routine characterization and advanced research applications.

Introduction

X-ray Absorption Spectroscopy (XAS) is a powerful element-specific technique for probing oxidation states, electronic structure, and local atomic environments. XANES (X-ray Absorption Near Edge Structure) provides information on oxidation state and coordination geometry, while EXAFS (Extended X-ray Absorption Fine Structure) reveals local atomic structure, including interatomic distances and coordination numbers.

Traditionally, routine XAS measurements have relied on synchrotron facilities, where access can be limited by availability and scheduling constraints. The Empyrean platform brings XAS into the laboratory, enabling direct access to high-quality XANES and EXAFS measurements for both routine characterization and advanced research applications.

Laboratory XAS on Empyrean

The Empyrean XAS solution (Figure 1) combines crystal analyzers, precision goniometer positioning, and a high-resolution detector to enable stable energy scanning across a broad energy range. The system supports measurements from 4-20+ keV, providing access to K-edges of transition-metal elements as well as L-edges of heavier elements.

The flexible design allows users to optimize measurements for either high intensity or high energy resolution through simple reconfiguration of the crystal optics. Measurement times range from minutes, for rapid screening experiments, to longer (several hours) acquisitions suitable for detailed EXAFS analysis.

[Empyrean XAS with numbered labelled parts detector.png] Empyrean XAS with numbered labelled parts detector.png

Figure 1. Empyrean laboratory XAS setup. (1) X-ray Tube, (2) Incident Beam Optics, (3) Positioning Stage, (4) Analyzer Crystals, (5) Diffracted Beam Optics, (6) 1Der Advanced Detector

Broad Elemental Coverage and Data Quality

The accessible energy range enables XAS measurements across a large portion of the periodic table, covering both K- and L-edges relevant to materials science, catalysis, energy storage, environmental science, and geology.

Representative measurements collected on Empyrean demonstrate the capability of the system across the accessible energy range. XANES spectra of transition-metal compounds clearly resolve oxidation-state-dependent edge shifts and small variations of the spectral features associated with changes in local electronic structure and atomic coordination. Multi-edge measurements can be performed within a single experiment, enabling simultaneous investigation of multiple elements and electronic states in complex materials. At higher energies, well-resolved EXAFS oscillations can provide access to local structural information, including coordination environments and interatomic distances.

Comparison with synchrotron measurements demonstrates excellent agreement in absorption edge positions, near-edge features, and EXAFS oscillations. These results show that laboratory XAS on Empyrean provides data quality suitable for both qualitative interpretation and quantitative analysis while offering the flexibility and accessibility of an in-house instrument.

[Figure 2 AN260623-xas-empyrean-xanes-exafs.png] Figure 2 AN260623-xas-empyrean-xanes-exafs.png

Figure 2. Periodic table showing the accessible K- and L-edges and data quality within the Empyrean XAS energy range.

Data Processing and Workflow

The Empyrean XAS solution is supported by dedicated software that streamlines the complete workflow from experiment planning to data interpretation. Built-in guidance assists with sample preparation, including optimization of sample absorption and dilution ratios, while automated acquisition routines simplify data collection and ensure measurement consistency.

Comprehensive data processing tools are integrated within the software environment, enabling efficient curation and analysis of XAS datasets. Available functions include scan alignment, detector linearity correction, deglitching, rebinning, background subtraction, and pre-edge and post-edge fitting with spectral normalization. These capabilities support both rapid screening experiments and detailed XANES and EXAFS investigations.

Designed for both new and experienced users, the software reduces the complexity of XAS measurements and enables rapid progression from sample preparation to scientific insight.

[Empyrean XAS - built for real experimental workflows process diagram.png] Empyrean XAS - built for real experimental workflows process diagram.png

Figure 3. Integrated software workflow for XAS measurements, covering sample preparation, data acquisition, and data processing.

Key Benefits

  • Laboratory access to high-quality XANES and EXAFS measurements
  • Broad energy coverage from 4-20+ keV
  • Sensitivity to oxidation state, electronic structure, and local coordination
  • Multi-edge measurements within a single experiment
  • Synchrotron-comparable data quality
  • Flexible switching between high-intensity and high-resolution measurement modes
  • Familiar Empyrean operation and workflow
  • Complementary XRD and XAS capabilities on the same platform

Conclusion

The Empyrean XAS solution enables routine laboratory-based XANES and EXAFS measurements across a broad elemental and energy range. By combining dedicated XAS hardware with high-quality data acquisition and analysis capabilities, the system delivers synchrotron-comparable performance while providing the accessibility, flexibility, and convenience of an in-house instrument. The ability to perform both XRD and XAS measurements on the same platform makes Empyrean a versatile solution for advanced materials characterization.