Comparison of O adsorption on Ni3Al (001), (011), and (111) surfaces through first-principles calculations

Synthesis of CaC2 and the Adsorption Mechanism of Alkaline Metals on the CaC2 Surface

“…Figure 4 shows the possible highly symmetric adsorption sites 28 The adsorption energy of Na and K adsorbed on the surface of CaC 2 (110) is as follows:…”

“…Figure shows the possible highly symmetric adsorption sites of Na or K atoms on the surface of CaC 2 (110), with a total of nine adsorption sites. Three of the sites on the top are the Ca on the top (T Ca ) and the C on the top (T C1 and T C2 ), two Ca–Ca bridge sites (B Ca1–Ca3 and B Ca1–Ca4 ), two Ca–C bridge sites (B Ca1–C1 and B Ca1–C2 ), and two triple Ca-2C hollow sites (H Ca2–2C and H Ca1–2C ).…”

Initial-Stage Oxidation of Ni3Al(100) and -(110) from Ab Initio Thermodynamics

“…For the Ni 3 Al(100) slab, our results show that after structural relaxation, the spacing change between the first and second Ni layers is −3.027% and that between the first Al and second Ni layers is −2.130%, which are similar to the previously calculated values of −2.859% and −2.466%, 24 while slightly different from the experimental value of −2.809% for the first and second Ni layers and a larger difference from the experimental value of 1.124% for the first Al and second Ni layers. 25 For the Ni 3 Al(110) slab, our results show that after structural relaxation, the spacing change between the first and second Ni layers is −11.261% and brween the first Al and second Ni layers is −9.992%, which are similar to the previously calculated values of −10.595% and −9.618%, 23 with a slight difference from the experimental values of −11.835% and −10.643%. 26 The percentage differences between the calculated and experimental values are probably due to the limited layers involved in the DFT calculations.…”

“…Ni 3 Al has an ordered cubic (L1 2 ) structure with the space group Pm3̅ m. Our calculated bulk lattice constant obtained from the energy minimization of the bulk Ni 3 Al unit cell using a Monkhorst−Pack mesh of (15 × 15 × 15) is 3.568 Å, which is in good agreement with the experimental value of 3.57 Å 22 and with previous calculations. 23 The Ni 3 Al(100) and -(110) surfaces are constructed by cleaving supercells made from the bulk Ni 3 Al. Successive slabs with the (2 × 2) surface unit cell and five atomic layers are separated by a vacuum region of 15 Å.…”

“…To verify our values, we also relax the Ni 3 Al(100) and Ni 3 Al(110) slabs and compare the results with the previously reported calculated results. 23,24 The interlayer separation is measured by the percentage of changes in relaxed distances and original distances. For the Ni 3 Al(100) slab, our results show that after structural relaxation, the spacing change between the first and second Ni layers is −3.027% and that between the first Al and second Ni layers is −2.130%, which are similar to the previously calculated values of −2.859% and −2.466%, 24 while slightly different from the experimental value of −2.809% for the first and second Ni layers and a larger difference from the experimental value of 1.124% for the first Al and second Ni layers.…”