Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance work on Wednesday 27th March 2019 from 11:00 AM to 1:00 PM (GMT).

During this time our website performance may be temporarily affected. We apologise for any inconvenience this might cause and thank you for your patience.


Issue 4, 2019
Previous Article Next Article

Nucleation of pseudo hard-spheres and dumbbells at moderate metastability: appearance of A15 Frank–Kasper phase at intermediate elongations

Author affiliations

Abstract

Crystal nucleation of repulsive hard-dumbbells from the sphere to the two tangent spheres limit is investigated at moderately high metastability by brute-force molecular dynamics simulations. Nucleation rates are in good agreement with previous simulations of hard-spheres and dumbbells. Icosahedral structures formed by twinned face-centred-cubic tetrahedra sharing five-fold symmetry axes and icosahedral centers are often found in spheres and dumbbells with either small (L/σ = 0.1 and 0.2) and large (L/σ = 1) elongations. These structures are incompatible with long range crystalline order but are able to survive up to quite large sizes. In contrast, at intermediate elongations (L/σ = 0.3), corresponding roughly to the bond length of molecular nitrogen, the fluid crystallizes into three distinct solid structures, namely, a low density plastic crystal, a hexagonal close-packed plastic crystal (with the same structure as β-N2), and an A15 Frank–Kasper phase (cP8 structure corresponding to δ-N2). At the lower pressures studied the hexagonal close packed plastic crystal is the most stable phase, but at the higher pressures the stable phase is an orientationally ordered solid designated as CP1 that is never spontaneously formed in our crystallization simulations.

Graphical abstract: Nucleation of pseudo hard-spheres and dumbbells at moderate metastability: appearance of A15 Frank–Kasper phase at intermediate elongations

Back to tab navigation

Publication details

The article was received on 04 Aug 2018, accepted on 12 Oct 2018 and first published on 12 Oct 2018


Article type: Paper
DOI: 10.1039/C8CP04964E
Citation: Phys. Chem. Chem. Phys., 2019,21, 1656-1670

  •   Request permissions

    Nucleation of pseudo hard-spheres and dumbbells at moderate metastability: appearance of A15 Frank–Kasper phase at intermediate elongations

    I. Zubieta, M. Vázquez del Saz, P. Llombart, C. Vega and E. G. Noya, Phys. Chem. Chem. Phys., 2019, 21, 1656
    DOI: 10.1039/C8CP04964E

Search articles by author

Spotlight

Advertisements