Chemical and magnetic properties of polycrystalline iron surface revealed by Auger electron holography, spectroscopy, and microscopy

Series of two-dimensional Auger electron intensity angular distributions (AIAD) were measured from a polycrystalline iron surface using a focused soft X-ray beam and a display-type analyzer. The Fe(110) surface was polycrystallized by annealing up to the Martensitic transition temperature in an ultrahigh vacuum condition. After cooling the sample to room temperature, the crystal orientations of the 2121 scanned points were determined by Fe LMM AIAD measurements. Domain formation of submm size was confirmed. The domains oriented in the [001] direction were found adjacent to the domain oriented in the [110] direction, suggesting that the Martensitic transition progressed according to the Bain relationship. The chemical and magnetic properties of domains with different surface orientations were characterized by combining diffraction measurements with X-ray absorption spectroscopy techniques. We show here how the surface oxidation reaction as well as the magnetization axis depend on the surface orientation.