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Density functional theory (DFT) studies are performed on the geometric structures, stability, electronic properties of the RhmPdn (m + n = 13) clusters. All the configurations are 13-atomic icosahedral structures, with an atom in the central site. Rh1Pd12 has Ih symmetry and relatively suitable stability and electronic properties among these clusters, with moderate stability and inter-atomic binding interaction as the representative system for the study of NO molecule adsorption and dissociation. NO molecule tends to be end-on adsorbed on Rh1Pd12 with its N atom connecting to metal atoms of the cluster, preferably at the hollow site to the top or bridge site. For the dissociation of NO as a key step in its reduction, the adsorption and dissociation of NO on Rh1Pd12 cluster are overall exothermic reactions from the energies of the free NO molecule and the cluster. Doping Rh in the pure cluster affects little on the adsorption energy and dissociation energy barrier but much on the relative energy (the energy reduction from the free NO molecule and cluster to the final state). [ABSTRACT FROM AUTHOR]

Janus transition metal dichalcogenides (TMDCs) type two-dimensional materials have been widely studied because of their unique asymmetrical structures and properties. In the preparation of Janus TMDCs, replacing the top layer S atoms of MoS2 with H atoms could yield unique Janus MoSH, which has been scarcely reported. In this work, the electronic, mechanical and piezoelectric properties of Janus MoSH are systematically studied using first principles calculations for the first time. The band structure of Janus MoSH is of metallic nature with two bands crossing the Fermi level. This material has a stable structure, and the Poison ratio ν > 1/3 indicates the good ductility. The relatively higher piezoelectric coefficients, e11 of −4.27 × 10−10 C/m and d11 of −5.09pm/V for Janus MoSH, compared with the typical piezoelectric semiconductor materials MoS2 (3.64 × 10−10 C/m and 3.73pm/V, respectively) may reflect suitable piezoelectric effect in the former. The above calculations may show that Janus MoSH would be potentially adopted as efficient sensors and piezoelectric components. [ABSTRACT FROM AUTHOR]

Based on density functional theory (DFT), the geometric structures, stability as well as electronic and spectral properties of P2On (1 ≤ n ≤ 10) clusters are studied by using the Gaussian 09 software. The energy gap of the clusters first increases and then decreases with the increasing number n of O atoms, and P2O6 exhibits the largest energy gap and hence the highest chemical stability among the clusters. On account of the largest distance between the two peaks on both side of the Fermi energy level in density of state (DOS) for P2O6 in the clusters, which may support the highest stability of this system. The ultraviolet–visible (UV–Vis) spectra are also calculated. P2O2 is likely to be applied as potential UV-absorbing materials in view of the relatively strong absorption in UV region. Meanwhile, P2O7 has the most extensive and strongest absorption in visible region and may exhibit the best visible light activity and potential visible light catalytic performance. [ABSTRACT FROM AUTHOR]