About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
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Symposium
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Ceramics and Glasses Modeling by Simulations and Machine Learning
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Presentation Title |
Lithium Dopant and Surface Effects on the Band Gap of Calcium Hexaboride (CaB6) Using DFT Methods |
Author(s) |
Roxana Morton, Alan Hirales, Victor R. Vasquez, Olivia A Graeve |
On-Site Speaker (Planned) |
Roxana Morton |
Abstract Scope |
Calcium hexaboride is part of the metal hexaborides (MB6) materials group which are well characterized compounds with Pm3m symmetry known for their low work functions, high melting points, low thermal expansion coefficients, high hardness, and chemical stability. On this work, the effects of surface anisotropy and the effect of lithium dopant on the electronic structure of different CaB6 surface configurations is analyzed. DFT calculations are performed using the plane-wave and pseudopotentials method. The band gap, band structure, and charge density at the surface of CaB6 are calculated to gain insight on the surface effects and the effect of Li dopant. The results show a reduced band gap on the surface structures in comparison to the bulk, indicating that the surface atomic tends to have a semi-metallic behavior, while the bulk it is known to be a semiconductor with a band gap of >1.0 eV. |