Related papers: Structure, superfluidity, and quantum melting of h…
The melting-like transition in sodium clusters Na_N, with N=55, 92, and 142 is studied by using constant-energy molecular dynamics simulations. An orbital-free version of the Car-Parrinello technique is used which scales linearly with…
We numerically model experiments in which large-scale vortex rings - bundles of quantized vortex loops - are created in superfluid helium by a piston-cylinder arrangement. We show that the presence of a normal fluid vortex ring together…
The design of moderators and cold sources of neutrons is a key point in research-reactor physics, requiring extensive knowledge of the scattering properties of very important light molecular liquids such as methane, hydrogen and their…
We report the observation of vortex formation upon the absorption of a thermal neutron in a rotating container of superfluid $^3$He-B. The nuclear reaction n + $^3$He = p + $^3$H + 0.76MeV heats a cigar shaped region of the superfluid into…
The melting-like transition in disordered sodium clusters Na_N, with N=92 and 142 is studied by using a first-principles constant-energy molecular dynamics simulation method. Na_142, whose atoms are distributed in two (surface and inner)…
A unique property of size-resolved metal nanocluster particles is their "superatom"-like electronic shell structure. The shell levels are highly degenerate, and it has been predicted that this can enable exceptionally strong…
In recent years, experimental data were published which point to the possibility of the existence of superfluidity in solid helium. To investigate this phenomenon theoretically we employ a hierarchy of equations for reduced density matrices…
Using molecular dynamics simulation technique, we have studied the melting behaviours of free, icosahedral PtN clusters in the size range of N=12-14. Voter and Chen version of an embedded-atom model, derived by fitting to experimental data…
First principle calculations have been performed to understand the experimentally observed size sensitive variations in the characteristics of heat capacities of gallium clusters [G. A. Breaux {\it et. al.} J. Am. Chem. Soc., {\bf 126},…
We theoretically investigate the ground-state properties of a molecular para-hydrogen (p-H2) film in which crystallization is energetically frustrated by embedding sodium (Na) atoms periodically distributed in a triangular lattice. In order…
First principle computer simulations of a thin parahydrogen film adsorbed on a silica substrate at low temperature (below 6 K) yield no evidence that the top layer is liquid and/or in the proximity of a superfluid transition, as claimed in…
An understanding of hydrogen diffusion on metal surfaces is important, not just for its role in heterogeneous catalysis and hydrogen fuel cell technology, but also because it provides model systems where tunneling can be studied under…
We discuss the dependence of the phase diagram of a hypothetical isotope of helium with nuclear mass less than 4 atomic mass units. We argue that with decreasing nucleus mass, the temperature of the superfluid phase transition (about 2.2 K…
We simulate the formation of a large X-ray cluster using a fully 3D hydrodynamical code coupled to a Particle-Mesh scheme which models the dark matter component. We focus on a possible decoupling between electrons and ions temperatures. We…
The molecular structure of the wetting layer of ice on Pt(111) is resolved using scanning tunneling microscopy (STM). Two structures observed previously by diffraction techniques are imaged for coverages at or close to completion of the…
Density functional molecular dynamics simulations have been carried out to understand the finite temperature behavior of Au$_{19}$ and Au$_{20}$ clusters. Au$_{20}$ has been reported to be a unique molecule having tetrahedral geometry, a…
A series of MD and DFT simulations were performed to investigate hydrogen self-clustering and retention in tungsten. Using a newly develop machine learned interatomic potential, spontaneous formation of hydrogen platelets was observed after…
Quantum effects in condensed matter normally only occur at low temperatures. Here we show a large quantum effect in high-pressure liquid hydrogen at thousands of Kelvins. We show that the metallization transition in hydrogen is subject to a…
Molecular Dynamics (MD) computer simulations are utilized to better understand the escape of neon from small (N=5) endohedral Ne@C60 clusters. Multiple runs at various temperatures are used to increase the reliability of our statistics. The…
Using molecular dynamics simulation, we investigate the slow dynamics of a supercooled binary mixture of soft particles interacting with a generalized Hertzian potential. At low density, it displays typical slow dynamics near its glass…