• D G Kanhere

Articles written in Pramana – Journal of Physics

• Stability of gold cages (Au16 and Au17) at finite temperature

We have employed ab initio molecular dynamics to investigate the stability of the smallest gold cages, namely Au16 and Au17, at finite temperatures. First, we obtain the ground state structure along with at least 50 distinct isomers for both the clusters. This is followed by the finite temperature simulations of these clusters. Each cluster is maintained at 12 different temperatures for a time period of at least 150 ps. Thus, the total simulation time is of the order of 2.4 ns for each cluster. We observe that the cages are stable at least up to 850 K. Although both clusters melt around the same temperature, i.e. around 900 K, Au17 shows a peak in the heat capacity curve in contrast to the broad peak seen for Au16.

• Structures, energetics and magnetic properties of (NiSn)$_{n}$ clusters with $n = 1–6$

We report the results of calculations which were performed to investigate equilibrium structures, electronic and magnetic properties of stoichiometric (NiSn)$_{n}$ clusters with $n = 1–6$ within the framework of density functional theory. The calculated results show that the structural arrangement of (NiSn)$_{n}$ clusters is dominated by the Ni–Sn and Ni–Ni interactions. We find that these binary clusters show significant variation in the geometries as compared to that of the host nickel clusters. The preference for tetrahedron unit of Ni3 Sn is seen in the lowest-energy configuration of these clusters. The multi-centre bonding between Ni atoms play an important role in stabilizing the stoichiometric Ni–Sn clusters. Doping of Sn atoms enhances the binding energy and reduces the ionization potential of nickel clusters. These binary clusters prefer the lowest spin state. For (NiSn)6 the magnetic moment is 0 𝜇B. The complete quenching of the cluster magnetic moment appears to be due to the antiferromagnetic alignment of atomic spins as revealed by the spin density plots.

• # Pramana – Journal of Physics

Current Issue
Volume 93 | Issue 5
November 2019

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019