Theoretical study of the structures and stabilities of iron clusters

Nanosized iron clusters investigated with in situ transmission electron microscopy

“…A transition from icosahedron to bcc rhombic dodecahedron is predicted for cluster sizes of approximately 2000 atoms. 21 In addition, another possibility for stable iron clusters can be cuboctahedron ͓face-centered-cubic ͑fcc͔͒ and truncated decahedron, 21 which could be feasible for clusters smaller than those in the present work.…”

“…After annealing and thermal break up of the oxide shell that surrounds the iron clusters, the crystal structure of the remaining clusters still remains bcc. The most stable structures 21 for medium-sized clusters ͑i.e., 100-10 000 atoms͒ calculated using an empirical manybody potential function are the bcc rhombic dodecahedron with 12 pseudoclose-packed ͕110͖ faces ͑having the lowest surface energy for bcc structures, 22 as is supported also by calculations using the density-functional theory͒, 23 and the icosahedron which is favorable for smaller clusters. A transition from icosahedron to bcc rhombic dodecahedron is predicted for cluster sizes of approximately 2000 atoms.…”

Entropic effects on the structure of Lennard-Jones clusters

“…However too many of the studies using this approach compare sub-optimal clusters. 19,25,26,28,29 For example, it is particularly common to compare Ino decahedra and fcc cuboctahedra to Mackay icosahedra, because they can have exactly the same sizes, even though the most stable sequences are likely to more closely resemble truncated octahedra and Marks 34 decahedra.…”

“…This method is commonly used and so crossover sizes have been estimated for LJ clusters, 19,20,21 metal clusters for elements such as tungsten, 22 nickel, 23 sodium, 24 lead, 25 , iron, 26 gold, 27 calcium and strontium, 28 rhodium and palladium, 29 and aluminium; 30 and molecular clusters for molecules such as N 2 , 31 CO 2 32 and SF 6 .…”

Structural dynamics of gas-phase molybdenum nanoclusters: A transmission electron microscopy study

“…It has been predicted that metal clusters with a bulk bcc structure would have a fcc structure for a small number of cluster atoms. 7,8 More specifically, x-ray diffraction experiments with molybdenum clusters have shown that a structural evolution occurs from amorphous→ fcc→ bcc structure as the number of constituent atoms increases. 9 It has been proposed that Mo clusters can have either the A15 or bcc structure.…”