Surface states of FeF2 (110) and its uncompensated magnetization

Abstract

Artículo de publicación ISIThe (110) surface of iron fluoride (FeF2) is especially relevant to the understanding of the exchange bias phenomenon, which has important applications in the sensor industry, and has been extensively explored, both theoretically and experimentally. Here we investigate this FeF2 surface by means of oh mine techniques. We compute the (110) surface reconstruction, energetics, magnetic moments, band structure, charge density and electron localization function, for the two possible terminations (Fe and F). The surface reconstruction modifies the atomic and electronic structure of the free surface, yielding magnetism of a magnitude of 0.1 mu(B) per surface unit cell. Moreover, the charge density also changes, which alters the bonding in the vicinity of the surface. All these changes are expected to be relevant for exchange bias, that is once a ferromagnetic layer is deposited on the FeF2 surface.National Science Foundation OCI-1053575 1003907 state of West Virginia (WVEPSCoR via the Higher Education Policy Commission) WVU Fondo Nacional de Investigaciones Cientificas y Tecnologicas (FONDECYT, Chile) 11110510 1150806 1130672 3140526 1120399 1130272 Financiamiento Basal para Centros Cientificos y Tecnologicos de Excelencia, Chile Donors of the American Chemical Society Petroleum Research Fund 54075-ND1

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