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Published on: February 11, 2012
Atomic structure of As(25)Si(40)Te(35) glass
1Institute of Physics, Chemnitz University of Technology, D-09107 Chemnitz, Germany.
Summary
This study reveals the atomic structure of glassy Arsenic-Silicon-Tellurium (As25Si40Te35). Reverse Monte Carlo simulations show a 3D network of twofold coordinated Tellurium, threefold coordinated Arsenic, and fourfold coordinated Silicon atoms.
Area of Science:
- Materials Science
- Solid State Chemistry
- Amorphous Materials Research
Background:
- Understanding the atomic structure of amorphous materials is crucial for predicting their properties.
- Chalcogenide glasses, like Arsenic-Silicon-Tellurium (As-Si-Te), are technologically relevant but their complex structures require advanced characterization.
Purpose of the Study:
- To elucidate the atomic-scale structure of glassy As(25)Si(40)Te(35).
- To determine partial pair distribution functions and coordination numbers within the glass network.
Main Methods:
- Utilized a combination of experimental techniques: x-ray diffraction, neutron diffraction, and extended x-ray absorption fine structure (EXAFS) spectroscopy.
- Employed reverse Monte Carlo (RMC) simulations for simultaneous modeling of multiple diffraction and spectroscopic data.
- Separated partial pair distribution functions and calculated coordination numbers.
Main Results:
- Successfully modeled four independent experimental measurements using RMC simulations.
- Determined the partial pair distribution functions for the As-Si-Te glass.
- Estimated coordination numbers for constituent atoms: Te (2-fold), As (3-fold), and Si (4-fold).
Conclusions:
- The atomic structure of As(25)Si(40)Te(35) glass is characterized by a robust three-dimensional network.
- The network consists of specifically coordinated Tellurium, Arsenic, and Silicon atoms, providing insights into glass stability and properties.
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