Spin–orbit Splitting and Magnetism of Icosahedral M@Ag12 Clusters (M = 3d and 4d atoms)

Exploring s-d, s-f, and d-f Electron Interactions in AgnCe+ and AgnSm+ by Chemical Reaction toward O2

We investigate gas-phase reactions of free Ag_nCe⁺ and Ag_nSm⁺ clusters with oxygen molecules to explore s-d, s-f, and d-f electron interactions in the finite size regime; a Ce atom has a 5d electron as well as a 4f electron, whereas a Sm atom has six 4f electrons without 5d electrons. In the reaction of Ag_nCe⁺ (n = 3-20), the Ce atom located on the cluster surface provides an active site except for n = 15 and 16, as inferred from the composition of the reaction products with oxygen bound to the Ce atom as well as from their relatively high reactivity. The extremely low reactivity for n = 15 and 16 is due to encapsulation of the Ce atom by Ag atoms. The minimum reactivity observed at n = 16 suggests that a closed electronic shell with 18 valence electrons is formed with a delocalized Ce 5d electron, while the localized Ce 4f electron does not contribute to the shell closure. As for Ag_nSm⁺ (n = 1-18), encapsulation of the Sm atom was observed for n ≥ 15. The lower reactivity at n = 17 than at n = 16 and 18 implies that an 18-valence-electron shell closure is formed with s electrons from Ag and Sm atoms; Sm 4f electrons are not involved in the shell closure as in the case of Ag_nCe⁺. The present results suggest that the 4f electrons tend to localize on the lanthanoid atom, whereas the 5d electron delocalizes to contribute to the electron shell closure.

Electron counting in cationic and anionic silver clusters doped with a 3d transition-metal atom: endo- vs. exohedral geometry

Cationic and anionic AgNM+/− (M = Sc–Ni) clusters are explored to examine the electron-counting rule. Among 18-valence-electron clusters, endohedrally doped ones are stable due to superatomic electron-shell closure involving delocalized 3d electrons.

Quantum-Chemical Design of Molecular Structures of Tetra-, Penta- and Hexanuclear Metal Clusters Containing Aluminum and 3d-Element Atoms

Various data on the structural and thermodynamic characteristics of polynuclear metal clusters containing atoms of aluminum and various d-elements with the general formula Al_nM_m where (n + m) is 4, 5, or 6, and which can be precursors for the formation of nanoparticles of elemental metals or intermetallic compounds, have been systematized and discussed. It has been noted that each of these metal clusters in principle is able to exist in very diverse structural isomers, differing significantly among themselves in terms of the total energy and spin multiplicity of the ground state, the number of which is determined by both the specific values of n and m, and the nature of d-elements in their compositions. The presence of very complex dynamics with respect to the changes of the individual thermodynamic characteristics of the metal clusters under consideration as well as the thermodynamic parameters of the reactions of their formation, depending on the nature of the d-element, were also ascertained. In the main, the given review is devoted to the authors’ works published over the last 10 years. Bibliography – 96 references.

Degradation of the transition metal@Pt core–shell nanoparticle catalyst: a DFT study

Electrocatalysts in acidic media face the issues of inactivation and degradation with complex thermodynamic processes.

Probing the structural, electronic and magnetic properties of AgnSc (n = 1–16) clusters

The structural, electronic and magnetic properties of Ag_nSc (n = 1–16) clusters have been studied on the basis of density functional theory and the CALYPSO structure prediction method.

Probing the Structural, Electronic, and Magnetic Properties of Ag n V (n = 1-12) Clusters

The structural, electronic, and magnetic properties of Ag _n V (n = 1-12) clusters have been studied using density functional theory and CALYPSO structure searching method. Geometry optimizations manifest that a vanadium atom in low-energy Ag_nV clusters favors the most highly coordinated location. The substitution of one V atom for an Ag atom in Ag _n + 1 (n ≥ 5) cluster modifies the lowest energy structure of the host cluster. The infrared spectra, Raman spectra, and photoelectron spectra of Ag _n V (n = 1-12) clusters are simulated and can be used to determine the most stable structure in the future. The relative stability, dissociation channel, and chemical activity of the ground states are analyzed through atomic averaged binding energy, dissociation energy, and energy gap. It is found that V atom can improve the stability of the host cluster, Ag₂ excepted. The most possible dissociation channels are Ag _n V = Ag + Ag _n - 1V for n = 1 and 4-12 and Ag _n V = Ag₂ + Ag _n - 2V for n = 2 and 3. The energy gap of Ag _n V cluster with odd n is much smaller than that of Ag _n + 1 cluster. Analyses of magnetic property indicate that the total magnetic moment of Ag _n V cluster mostly comes from V atom and varies from 1 to 5 μ _B. The charge transfer between V and Ag atoms should be responsible for the change of magnetic moment.