Nuclear spin configurations in the (rare earth) Fe2intermetallics

57 Fe nuclear spin configurations in the (rare earth)Fe 2 intermetallics have been deduced from Mossbauer experiments on polycrystalline samples. It is shown that the 57 Fe nuclei do not, in general, point exactly along the direction of magnetization M. For example the nuclear spins in DyFe 2 and HoFe 2 at room temperature are tipped away from the (001) magnetic axis by about 4 degrees . The origin of this tipping is traced to the local dipolar fields in these compounds. The situation in intermetallics with a (111) direction of magnetization is more complex because of the presence of two nonequivalent ion sites. The case of TbFe 2 is dealt with in some detail and it is shown that the nuclei in 'triangular nets' are collinear with M whereas those in 'kagome nets' make a small angle with the (111) direction of magnetization. Some comments are also made on the possibility of magnetically induced electric field gradients in these compounds.