Electron correlation effects in boron clusters BnQ (for Q=-1,0, 1 and n ≤13) based on quantum Monte Carlo simulations

We present all-electron quantum Monte Carlo simulations on the anionic, neutral, and cationic boron clusters BnQ with up to 13 atoms (Q=-1,0,+1 and n≤ 13). Accurate total energies of these...

Structural transformations in boron clusters induced by metal doping

Would it be possible to eventually derive a simple methodology to predict the structure adopted by boron clusters based on its structural transformation induced by the doping with one or two metal atoms?

Monovalent lanthanide(I) in borozene complexes

Lanthanide (Ln) elements are generally found in the oxidation state +II or +III, and a few examples of +IV and +V compounds have also been reported. In contrast, monovalent Ln(+I) complexes remain scarce. Here we combine photoelectron spectroscopy and theoretical calculations to study Ln-doped octa-boron clusters (LnB8−, Ln = La, Pr, Tb, Tm, Yb) with the rare +I oxidation state. The global minimum of the LnB8− species changes from Cs to C7v symmetry accompanied by an oxidation-state change from +III to +I from the early to late lanthanides. All the C7v-LnB8− clusters can be viewed as a monovalent Ln(I) coordinated by a η8-B82− doubly aromatic ligand. The B73−, B82−, and B9− series of aromatic boron clusters are analogous to the classical aromatic hydrocarbon molecules, C5H5−, C6H6, and C7H7+, respectively, with similar trends of size and charge state and they are named collectively as “borozenes”. Lanthanides with variable oxidation states and magnetic properties may be formed with different borozenes.

A theoretical study on photo absorption in silicon decorated boron clusters (BnSi, n=7-10)

In this work, we have studied the optical absorption spectra of small boron clusters doped with single silicon atom (BnSi, n=7-10) and is reported employing CAM-B3LYP functional with 6-311+G(d) basis –set within the framework of time dependent density functional study (TD-DFT). We have computed excitation energy, oscillator strength, wavelength and the corresponding orbital transitions associated with a given oscillator strength. Analysis of optical absorption spectra of studied clusters shows that most of the absorption peaks are found in the ultraviolet-visible (UV-Vis) region (200 nm-700 nm). The major peaks are found to fall in UV region along with some weaker peaks at visible region. The most intense peak is recorded for B8Si cluster at 232 nm and oscillator strength of 0.084. This peak is associated with the orbital transition from H-4→L+1.

Theoretical Design of Novel Boron-Based Nanowires via Inverse Sandwich Clusters

Borophene has important application value, boron nanomaterials doped with transition metal have wondrous structures and chemical bonding. However, little attention was paid to the boron nanowires (NWs). Inspired by the novel metal boron clusters Ln2Bn− (Ln = La, Pr, Tb, n = 7–9) adopting inverse sandwich configuration, we examined Sc2B8 and Y2B8 clusters in such novel structure and found that they are the global minima and show good stability. Thus, based on the novel structural moiety and first-principles calculations, we connected the inverse sandwich clusters into one-dimensional (1D) nanowires by sharing B−B bridges between adjacent clusters, and the 1D-Sc4B24 and 1D-Y2B12 were reached after structural relaxation. The two nanowires were identified to be stable in thermodynamical, dynamical and thermal aspects. Both nanowires are nonmagnetic, the 1D-Sc4B24 NW is a direct-bandgap semiconductor, while the 1D-Y2B12 NW shows metallic feature. Our theoretical results revealed that the inverse sandwich structure is the most energy-favored configuration for transition metal borides Sc2B8 and Y2B8, and the inverse sandwich motif can be extended to 1D nanowires, providing useful guidance for designing novel boron-based nanowires with diverse electronic properties.

The Crystal Structures of Two Hydro-closo-Borates with Divalent Tin in Comparison: Sn(H2O)3[B10H10] · 3 H2O and Sn(H2O)3[B12H12] · 4 H2O

Single crystals of Sn(H2O)3[B10H10] · 3 H2O and Sn(H2O)3[B12H12] · 4 H2O are easily accessible by reactions of aqueous solutions of the acids (H3O)2[B10H10] and (H3O)2[B12H12] with an excess of tin metal powder after isothermal evaporation of the clear brines. Both compounds crystallize with similar structures in the triclinic system with space group P$$\bar{1 }$$ 1 ¯ and Z = 2. The crystallographic main features are electroneutral $${}_{\infty }^{1} \{$$ ∞ 1 { Sn(H2O)3/1[B10H10]3/3} and $${}_{\infty }^{1} \{$$ ∞ 1 { Sn(H2O)3/1[B12H12]3/3} double chains running along the a-axes. Each Sn2+ cation is coordinated by three water molecules of hydration (d(Sn–O) = 221–225 pm for the B10 and d(Sn–O) = 222–227 pm for the B12 compound) and additionally by hydridic hydrogen atoms of the three nearest boron clusters (d(Sn–H) = 281–322 pm for the B10 and d(Sn–H) = 278–291 pm for the B12 compound), which complete the coordination sphere. Between these tin(II)-bonded water and the three or four interstitial crystal water molecules, classical bridging hydrogen bonds are found, connecting the double chains to each other. Furthermore, there is also non-classical hydrogen bonding between the anionic [BnHn]2− (n = 10 and 12) clusters and the crystal water molecules pursuant to B–Hδ−$$\cdots$$ ⋯ δ+H–O interactions often called dihydrogen bonds.

Study the structure, stability and CO2 adsorption of the ScVB5 cluster

A combination of genetic algorithm and density functional theory (GA-DFT) was used to calculate the minimum structures of ScVB5 clusters. The thirteen isomers of ScVB5 cluster were investigated at the level of PBE/def2-TZVPP, TPSSh/def2-TZVPP, and TPSSh/def2-QZVP levels. The relative energies, the structural geometry, ionization energy, affinity energy of neutral isomers were reported. The ScVB5 cluster can be formed by adding atom into smaller clusters. The proposed structure of ScVB5 cluster for CO2 treatment is a pentagonal bipyramid in the Cs symmetry with vanadium atom at one of the vertices and scandium atom in the base of bipyramid. The favor position for adsorp CO2 by the ScVB5 cluster were at around of Sc and V atoms. The dual transition metal-doped boron clusters can interact with CO2 molecules stronger than pure boron clusters.