title: Size Dependent Phase Diagrams of Nickel-Carbon Nanoparticles.
abstract: The carbon rich phase diagrams of nickel-carbon nanoparticles, relevant to catalysis and catalytic chemical vapor deposition synthesis of carbon nanotubes, are calculated for system sizes up to about 3 nm (807 Ni atoms). A tight binding model for interatomic interactions drives the grand canonical Monte Carlo simulations used to locate solid, core shell and liquid stability domains, as a function of size, temperature, and carbon chemical potential or concentration. Melting is favored by carbon incorporation from the nanoparticle surface, resulting in a strong relative lowering of the eutectic temperature and a phase diagram topology different from the bulk one. This should lead to a better understanding of the nanotube growth mechanisms.
authors.affiliation: Centre Interdisciplinaire de Nanoscience de Marseille, Aix-Marseille University and CNRS, Campus de Luminy, Case 913, F-13288 Marseille, France.
authors.forename: Y
authors.initials: Y
authors.lastname: Magnin
authors.affiliation: Centre Interdisciplinaire de Nanoscience de Marseille, Aix-Marseille University and CNRS, Campus de Luminy, Case 913, F-13288 Marseille, France.
authors.forename: A
authors.initials: A
authors.lastname: Zappelli
authors.affiliation: Laboratoire d'Etude des Microstructures, ONERA-CNRS, BP 72, F-92322 Châtillon, France.
authors.forename: H
authors.initials: H
authors.lastname: Amara
authors.affiliation: Laboratoire d'Etude des Microstructures, ONERA-CNRS, BP 72, F-92322 Châtillon, France.
authors.forename: F
authors.initials: F
authors.lastname: Ducastelle
authors.affiliation: Centre Interdisciplinaire de Nanoscience de Marseille, Aix-Marseille University and CNRS, Campus de Luminy, Case 913, F-13288 Marseille, France.
authors.forename: C
authors.initials: C
authors.lastname: Bichara