Modeling and X-ray Analysis of Defect Nanoclusters Formation in B4C under Ion Irradiation

Abstract

In the presented work, B4C was irradiated with xenon swift heavy ions at the energy of 167 MeV. The irradiation of the substrate was done at room temperature to a fluence of 3.83 × 1014 ion/cm2. The samples were then analyzed with the X-ray diffraction technique to study the structural modification, as it can probe the region of penetration of xenon atoms due to the low atomic number of the two elements involved in the material under study. The nano-cluster formation under ion irradiation was observed. Positron lifetime (PLT) calculations of the secondary point defects forming nanoclusters and introduced into the B4C substrate by hydrogen and helium implantation were also carried out with the Multigrid instead of the K-spAce (MIKA) simulation package. The X-ray diffraction results confirmed that the sample was B4C and it had a rhombohedral crystal structure. The X-ray diffraction indicated an increase in the lattice parameter due to the Swift heavy ion (SHI) irradiation. In B12-CCC, the difference between τ with the saturation of H or He in the defect is nearly 20 ps. Under the same conditions with B11C-CBC, there is approximately twice the value for the same deviation.

Mechanism of formation water molecules and chemical bonds in Leptothrix materials

“…The case that was not considered in our previous work (Mirzayeva et al, 2023b) is the accumulation of water molecules in the vacancy clusters of the two materials that we consider (Fe2O3 and Fe3O4). The unit cell and spatial parameters we used are fixed as follows: for Fe2O3: a, b, c = 9.56 Ǻ α, β, γ = 90° / Ia/3 (206), for Fe3O4: a, b, c = 8.44 Ǻ α, β, γ = 90° / Fd/3m (229) (Agayev et al, 2020;Mirzayeva et al, 2019;2022a). Two water molecules were added in both cases in a vacancy cluster of two iron vacancies.…”