ELECTRONIC-STRUCTURE OF FCC FE-MN ALLOYS .1. CHARGE-DENSITY MEASUREMENTS

X-ray measurements of the structure factors of the paired reflections (333)-(511), (442)-(600) and (551)-(711) have been performed on the FCC alloy Fe//6//6Mn//3//4. The ratios of the structure factors show that the charge density of this alloy is very nearly spherical with only a small deviation toward T//2//g symmetry. The results of this experiment have been compared with similar x-ray measurements on Fe//7//0Ni//3//0 and with spin-density measurements on the Fe-Ni system. From an analysis of the experimental charge and spin-density anisotropies it is deduced that while the charge density of the high-spin state of FCC Fe and Mn has a preference for T//2//g symmetry, the low-spin state of FCC Fe preferentially has E//g symmetry.