Abstract
Permalloy is an important material in a wide variety of magnetic systems, most notably in GMR
read-heads. However, despite this great interest its properties are not fully understood. For an in
depth analysis of important physical properties as e.g. electric transport or magnetic anisotropy
a detailed understanding of the distribution of magnetic moments on an atomic level is necessary.
Using our first principles Locally Self-consistent Multiple Scattering (LSMS) method we calculate the
magnetic ground state structure for a large super-cell model of Permalloy. Our code allows us to solve
both the usual non-relativistic Schrdinger equation as well as the fully relativistic Dirac equation
and to find the magnitude and direction of the magnetic moments at each atomic site. While the
non-relativistic calculation yields a collinear ground state in accordance with previous calculations,
we find the ground state for the fully relativistic calculation to be slightly non-collinear. We also
investigate the influence of variations in the iron concentration on the distribution of magnetic
moments.
