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Zintl (group IV elements) clusters with a special number of valence electrons often exhibit extraordinary structures and chemical bonding patterns, and the stability of them is rationalised by the Wade-Mingos rule. However, this rule is still limited for some Zintl clusters. Here, we find that the potential energy surface of PtSn5 has a single deep funnel, which leads down to the octahedron of the global minimum. The AIMD simulations demonstrate that the octahedral PtSn5 still has a good thermal stability at 1000 K. The molecular orbitals and AdNDP analyses reveal that the 20 valence electrons from five Sn atoms of the PtSn5 fill superatomic shells resulting in an electronic configuration of 1S21P61D102S2, and the electronic structure of the Pt atom is d10, well following the magic number of the Jellium model. The result is further confirmed by the density of states and the localised orbital locator. After the CO molecule is adsorbed on the PtSn5, it prefers to be located at the Pt atom. Due to the charge-transfer effect, the C–O bond length and stretching frequency appear to change significantly. Our work opens up the study on the Jellium model for Zintl clusters. [ABSTRACT FROM AUTHOR]

Metalloid gold clusters have unique properties with respect to size and structure and are key intermediates in studying transitions between molecular compounds and the bulk phase of the respective metal. In the following, the synthesis of the all‐phosphine protected metalloid cluster Au20(tBu3P)8, solely built from gold atoms in the oxidation state of 0 is reported. Single‐crystal X‐ray analysis revealed a highly symmetric hollow cube‐octahedral arrangement of the gold atoms, resembling gold bulk structure. Quantum‐chemical calculations illustrated the cluster can be described as a 20‐electron superatom. Optical properties of the compound have shown molecular‐like behavior. [ABSTRACT FROM AUTHOR]

We investigate the structural, surface and electronic properties of small silicon clusters Si n (for n = 2 to 15) using HF, DFT and FN-DMC calculations. We analyze the atomic configurations, surface properties and electronic structures and show that the radius and average surface area of the clusters can be modeled by a Jellium-type model. We found that the surface tension σ of the clusters decreases with increasing cluster size in the range of the clusters under investigation. An estimate of the surface tension for bulk silicon yields σ b u l k = 0. 88 (3) J/m2 in agreement with recent experiments. The average bond length of the clusters shows a non-monotonic behavior. Smaller clusters exhibit a high spin state influenced by electron correlation, especially during the 2D to 3D structural transition, which occurs at n = 4 to n = 5. We also find that the Si 4 , Si 10 and Si 12 clusters exhibit enhanced stability due to electron correlation. Our results are consistent with the experiments on bond length, binding energy and dissociation energy. [Display omitted] • Surface Tension Dynamics: Revealing how surface tension decreases with increasing cluster size. • Size-Dependent Bond Length: Identifying non-monotonic bond length changes and spin state influences during the 2D to 3D transition. • Enhanced Cluster Stability: Demonstrating the exceptional stability of Si 4 , Si 10 , and Si 12 clusters due to electron correlation. [ABSTRACT FROM AUTHOR]

The Bohm–Staver description of sound waves in metals in the jellium model is generalized by taking into account not only the self-consistent electric field but also the second correlation moment of internal electric field that provides shear elasticity. The system of linearized equations that contains the second correlation moment of the field as a new variable is built. The wave equation is worked out and the velocities of longitudinal and transverse sound are found. The estimation of the field correlation value through the sublimation heat and the electronic Fermi-gas energy is offered for the metals. The velocities of transverse sound are found, which matches well the velocity obtained from the shear modules. [ABSTRACT FROM AUTHOR]

The reduction of (nBu3P)AgCl with LiBH(sBu)3 in toluene gives the metalloid silver cluster Ag64(PnBu3)16Cl6 (1) as dark red, temperature‐ and light‐sensitive single crystals in high yield. 1 is the largest structurally characterized metalloid silver cluster exhibiting chlorine and phosphine substituents only. The silver atoms in 1 show an overall brick‐shape arrangement, where structural resemblance to the close‐packed fcc and hcp structures is realized. Within 1 a 58 electron closed shell system is present. The light sensitivity renders 1 as a model compound for the primary seeds of the photo process, whereby this sensitivity, together with the high‐yield synthesis show that 1 is a perfect starting compound for further investigations like silver‐plating processes. [ABSTRACT FROM AUTHOR]

The reduction of (nBu3P)AgCl with LiBH(sBu)3 in toluene gives the metalloid silver cluster Ag64(PnBu3)16Cl6 (1) as dark red, temperature‐ and light‐sensitive single crystals in high yield. 1 is the largest structurally characterized metalloid silver cluster exhibiting chlorine and phosphine substituents only. The silver atoms in 1 show an overall brick‐shape arrangement, where structural resemblance to the close‐packed fcc and hcp structures is realized. Within 1 a 58 electron closed shell system is present. The light sensitivity renders 1 as a model compound for the primary seeds of the photo process, whereby this sensitivity, together with the high‐yield synthesis show that 1 is a perfect starting compound for further investigations like silver‐plating processes. [ABSTRACT FROM AUTHOR]

The potential application of the jellium model as guidance in the rational design of bimetallic superalkali cations is examined under gradient‐corrected density functional theory for the first time. By using Li, Mg, and Al as atomic building blocks, a series of bimetallic cationic clusters with 2, 8, 20, and 40 valence electrons are obtained and investigated. As the corresponding neutral clusters tend to lose one valence electron to achieve closed‐shell states in the jellium model, these studied cations exhibit much lower vertical electron affinities (EAvert, 3.42–4.95 eV) than the ionization energies (IEs) of alkali metal atoms, indicating their superalkali identities. The high stability of these cationic clusters is guaranteed by their considerable HOMO–LUMO gaps and binding energies per atom. Moreover, the feasibility of using the designed superalkalis as efficient reductants to activate CO2 and N2 molecules and as stable building blocks to assemble ionic superatom compounds is explored. Therefore, this study may provide an effective method for obtaining various metallic superatoms with extensive applications on the basis of the simple jellium rule. Bimetallic superalkali design: Using density functional theory, the possibility of using the jellium model (see figure) to guide the rational design of bimetallic superalkali cations is examined, and their potential applications are also explored. [ABSTRACT FROM AUTHOR]

The chemical potential and the work function of an aluminium metal film which is in the vacuum (1) and on a dielectric substrate (2) are obtained using the model of non-interacting electrons confined by an asymmetric rectangular potential well. For the first time, these two characteristics are calculated with correct taking into account the electroneutrality condition. As a result, the values of the chemical potential and the work function tend to their bulk values upon increasing the film thickness. The presence of a dielectric substrate leads to a small shift in the values of these characteristics. [ABSTRACT FROM AUTHOR]

The chemical potential of a metal film within the jellium model taking into account the Coulomb interaction between electrons is calculated. The surface potential is modelled as the infinite rectangular potential well. The behaviour of the chemical potential as a function of the film thickness is studied, the quantum size effect for this quantity is analysed. It is shown that taking into account the Coulomb interaction leads to a significant decrease of the chemical potential and to an enhancement of the quantum size effect. [ABSTRACT FROM AUTHOR]

Genetic algorithm combined with the semi-empirical Hamitonian AM1/PM3 is used to search the low energy isomers of AlSi (n = 3, 5, m ≤ 3 and n = 4, m ≤ 4) and the charged clusters with 20 and 28 valence electrons. The candidate structures were optimized by the density functional theory PBE0 and B3LYP models with the triply split basis sets including polarization functions. The electronic structures show that Al-Si binary clusters behave like metal clusters. The molecular orbitals accord with that predicted by the jellium model, and the electron localization function shows the valence electrons are delocalized over the entire clusters. The clusters having 20 and 28 valence electrons exhibit pronounced stabilities and large energy gaps. The 20 valence electrons of AlSi and AlSi , AlSi form closed shells 1 S 1 P 2 S 1 D . AlSi and AlSi have oblate structures and the P, D, F levels spilt considerably in these clusters. The electron density distributions suggest that doping silicon in the aluminum clusters enhances the stability considerably. [ABSTRACT FROM AUTHOR]

A BNSi cage is formed upon substitution of Si sites of rhombus faces of the pure Si cluster by B and N atoms. Doping by the ion Mn leads to the hetero-silicon fullerene BNSiMn which comprises three rhombi (BNBN, SiB and SiN) and four pentagons (two SiBN and two SiBN). Hetero-atoms form polarized Si-N and Si-B bonds as indicated by electron localization function (ELF) maps and NBO charges. The Mn center connects the BNSi cage by ionic interactions. Valence electrons of BNSiMn occupy a shell configuration of [1S 1P 1D 1F 1G 2S 2P 2D] and induce a certain thermodynamic stability. The high spin of the Mn metal cation is completely quenched within the hetero-Si fullerene. [ABSTRACT FROM AUTHOR]

In this work we have applied the recently formulated self-compressed inhomogeneous stabilized jellium model [51] to describe the equilibrium electronic and geometric properties of atomic-closed-shell simple metal clusters of Al N ( N = 13, 19, 43, 55, 79, 87, 135, 141), Na N , and Cs N ( N = 9, 15, 27, 51, 59, 65, 89, 113). To validate the results, we have also performed first-principles pseudo-potential calculations and used them as our reference. In the model, we have considered two regions consisting of “surface” and “inner” ones, the border separating them being sharp. This generalization makes possible to decouple the relaxations of different parts of the system. The results show that the present model correctly predicts the size reductions seen in most of the clusters. It also predicts increase in size of some clusters, as observed from first-principles results. Moreover, the changes in inter-layer distances, being as contractions or expansions, are in good agreement with the atomic simulation results. For a more realistic description of the properties, it is possible to improve the method of choosing the surface thicknesses or generalize the model to include more regions than just two. [ABSTRACT FROM AUTHOR]

Using approximation of a uniform background (the jellium model) for a condensed dispersed phase, the analytical expressions describing a spatial distribution of the potential of the electric field and electron concentration in the low-temperature plasma at equilibrium which contains hollow spherical microparticles are obtained. The influence of heating temperature of plasma on the above distributions is studied, and the dependencies of the charge on microparticle radius, the size of the microparticle cavity and the absolute temperature of plasma are calculated. It is shown that electrons can be emitted not only into the surrounding plasma but also into the cavity of the particles. [ABSTRACT FROM AUTHOR]

In this work, we present negative-ion fractions as a function of exit velocity and angle after keV-energy negative oxygen and carbon ions scattering on a highly oriented pyrolytic graphite (HOPG) surface, at a scattering angle of 38°. The negative-ion fractions increase monotonously with the increase of exit velocity for specular scattering, while negative-ion fractions present a bell-shaped dependence on exit angle. In order to gain further insight into the nature of charge transfer on HOPG, a modified charge transfer model involving the contribution of positive ions has been proposed and roughly reproduced the velocity and angle dependences of negative-ion fractions. [ABSTRACT FROM AUTHOR]