Partial spin frustration system in the ordered Mn3Pt alloy

Abstract Mn 3 Pt alloy has a special magnetic structure, which is considered that one third of Mn atoms have no magnetic moment. We found that the lattice slightly distorts to a tetragonal structure and our neutron scattering data in the F-phase show inelastic diffuse scattering located along the first Brillouin zone boundary of the FCC-structure, indicating that the one third of Mn spins fluctuate dynamically with strong correlations. The Mn 3 Pt alloy has a partial spin frustration. Coexistence of static collinear spin structure and dynamical spins in the F-phase is a characteristic of the ordered Mn 3 Pt alloy.