Magnetic structure of (Fe0.97Cr0.03)(2)P

Magnetic behaviour of di-metal iron phosphide with a small substitution of iron by chromium, (Fe0.97Cr0.03)(2)P, has been studied using SQUID magnetom etry and powder neutron diffraction. It is paramagnetic at temperatures abo ve similar to 180 K with persisting short range ferromagnetic (FM) order. A t lower temperatures three different regions of magnetic behaviour are iden tified. FM order evolves in the region 180 K - 120 K but much more slowly a nd with much less magnetic moments than in Fe2P. In the region 120 K - 50 K negative exchange interactions gain some importance leading to a loss of F M order. Below 50 K FM interactions again dominate. Pinning centres influen ce the behaviour at low temperature up to similar to 100 K.