A density functional theory investigation on Au 9 M 2+ (M = Sc - Ni) clusters: structure, stability, electronic properties, and hydrogen adsorption Ngo Thi Lan 1,2 , Nguyen Thi Mai 1 , Nguyen Van Dang 2 and Nguyen Thanh Tung 1,* 1 Institute of Materials Science and Graduate University of Science and Technology, Vietnam Academy of Science and Technology, Vietnam, 2 Institute of Science and Technology, Thai Nguyen University of Science, Vietnam *Email: tungnt@ims.vast.ac.vn The last decades have witnessed an increasing interest in the hydrogen adsorption on nanoclusters up to few tens of atoms owing to their huge potential as building blocks for nanostructured materials with exciting catalytic and energy-storage applications [1] Among them, Au 10 2+ has been found extremely stable showing a superatomic behavior and can be considered as the smallest copy of the golden pyramid Au 20 . In this work, we further explore superatomic clusters as analogues of more complex molecules by doping Au 10 2+ cluster with a 3 d transition metal atom. In similarity to their sister Au 19 M, the structural evolution of Au 9 M 2+ is ruled by the bond strength and can be generalized into two motifs: the endohedrally doped cage-like structure for lighter dopants (M = Sc and Ti) and the slightly distorted tetrahedral structure for heavier ones. With a largest spin magnetic moment of 5 μB, the exceptionally stable Au 9 Cr 2+ is identified as a potential magnetic superatom and would be beneficial for further theoretical and experimental studies [2]. The interaction of Au 9 M 2+ clusters toward H 2 is found strongly dependent on the transition metal impurity. Au 9Sc 2+ , Au 9 Ti 2+ , Au 9 Mn 2+ , and Au 9 Fe 2+ clusters thermodynamically prefer the dissociative adsorption of H 2 with a certain barrier of energy while the molecular adsorption is favored for Au 9 V 2+ , Au 9 Cr 2+ , Au 9 Co 2+ , and Au 9 Ni 2+ clusters [3]. A comprehensive analysis shows that the geometric structure of clusters, the relative electronegativity, and the coordination number of the impurity play a decisive role in determining the preferred adsorption configuration. References 1. Y. Tsuji, Y. Yoshioka, M. Hori, and K. Yoshizawa, Topics in Catalysis 65, 215 (2022) 2. N. T. Lan, N. T. Mai, D. D. La, N. M. Tam, S. T. Ngo, N. T. Cuong, Ng. V. Dang, T. T. Phung, Ng. T. Tung, Chem. Phys. Lett. 793, 139451 (2022). 3. Ngo Thi Lan, Nguyen Thi Mai, Nguyen Van Dang, and Nguyen Thanh Tung, “Density functional study of size-dependent hydrogen adsorption on Au 9 M 2+ (M = Sc-Ni) clusters”, ACS Omega (to be published).
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