Abstract:

A high-pressure phase of iron, double-layer hexagonal close-packed (DHCP) structure, is observed upon pulsed-laser ablation of an iron target in liquid under the conditions of room temperature and ambient pressure, and meanwhile DHCP iron nanocrystals with 10–20 nm diameter are prepared. The magnetism measurements of the prepared nanocrystals indicate that DHCP iron nanocrystals are nonferromagnetic. The stability of DHCP iron nanocrystals under normal temperature and pressure is attributed to the nanosized confinement effect of nanocrystals.