Magnetic structures of small Fe, Mn, and Cr clusters supported on Cu(111): Noncollinear first-principles calculations

摘要: The magnetic structures of small clusters Fe, Mn, and Cr supported on a Cu(111) surface have been studied with noncollinear first-principles theory. Different geometries such as triangles, pyramids, wires are considered the cluster sizes varied between two ten atoms. calculations performed using real-space linear muffin-tin orbital method. Fe found to order ferromagnetically regardless geometry. For Mn clusters, antiferromagnetic exchange interactions nearest neighbors cause collinear ordering when geometry allows it. If antiferromagnetism is frustrated by geometry, found. A comparison calculated ground states obtained from simplified Heisenberg Hamiltonians show that interaction varies for different atoms in result local structure.