Metal-Insulator Transition Induced by Spin Reorientation in FeSe Grain Boundaries.

FeSe exists as a hexagonal NiAs-like crystal structure with a large number of ordered intrinsic vacancies. It is an ideal candidate for studying the effect of defects on properties such as magnetism and electrical transport. In this work, highly crystalline FeSe with the 3c crystal structure was synthesized by a solid-state reaction.