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Updated: May 31, 2026
07:08
In Situ Synthesis of Gold Nanoparticles without Aggregation in the Interlayer Space of Layered Titanate Transparent Films
Published on: January 17, 2017
Thermal dependent anharmonicity effects on gold bulk studied by extended x-ray-absorption fine structure
T Comaschi1, A Balerna, S Mobilio
1Dipartimento di Fisica 'E Amaldi', Università Roma TRE, via della Vasca Navale 84, I-00146 Roma, Italy.
Summary
This study reports gold (Au) bulk structural parameters using extended x-ray absorption fine structure (EXAFS) spectroscopy. The findings align with prior research and introduce a new method for analyzing atomic vibrations.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Spectroscopy
Background:
- Understanding the structural dynamics of bulk gold (Au) is crucial for various applications.
- Accurate determination of interatomic forces and atomic vibrations is essential for materials modeling.
Purpose of the Study:
- To determine the structural parameters of the first five coordination shells of Au bulk.
- To evaluate effective force constants and analyze atomic vibrations using EXAFS data.
- To propose a novel method for determining mean squared relative displacements.
Main Methods:
- High-accuracy L(3)-edge extended x-ray absorption fine structure (EXAFS) spectroscopy.
- Data acquisition across a temperature range of 20-300 K.
- Comparison with X-ray diffraction data and phonon dispersion curves.
Main Results:
- Structural parameters for the first five coordination shells of Au bulk were accurately determined.
- Effective second and third-order force constants derived from EXAFS data are consistent with phonon calculations.
- Mean squared relative displacements were calculated, and a new method for their determination was proposed.
Conclusions:
- EXAFS spectroscopy provides reliable structural information for bulk gold.
- The study validates the use of EXAFS for calculating interatomic force constants.
- A new approach enhances the capability to study atomic vibrations, even without X-ray diffraction data.
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