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arXiv · 1904.03021

Generation of ground state structures and electronic properties of ternary Al$_x$Ti$_y$Ni$_z$ clusters (x+y+z=6) with a two-stage DFT global search approach

Pin Wai Koh·Tiem Leong Yoon·Thong Leng Lim·Yee Hui Robin Chang·Eong Sheng Goh
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Abstract

The structural and electronic properties of ternary AlxTiyNiz clusters, where x, y, and z are integers and x + y + z = 6 are investigated. Both SVWN and B3LYP exchange-correlation functionals are employed in a two-stage density functional theory (DFT) calculations to generate these clusters. In the first stage, a minimum energy cluster structure is generated by an unbiased global search algorithm coupled with a DFT code using a light exchange-correlation functional and small basis sets. In the second stage, the obtained cluster structure is further optimized by another round of global minimization search coupled with a DFT calculator using a heavier exchange-correlation functional and more costly basis set. Electronic properties of the structures are illustrated in the form of a ternary diagram. Our DFT calculations find that the stability of the clusters increases with the increment in the number of constituent nickel atoms. These results provide a new insight to the structure, stability, chemical order and electronic properties for the ternary alloy nanoclusters.

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Pin Wai Koh, Tiem Leong Yoon, Thong Leng Lim, Yee Hui Robin Chang, Eong Sheng Goh. 2019-04-04. Generation of ground state structures and electronic properties of ternary Al$_x$Ti$_y$Ni$_z$ clusters (x+y+z=6) with a two-stage DFT global search approach. https://arxiv.org/abs/1904.03021

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