Magnetic properties of R/sub 2-x/R/sub x/'Co$sub 17$ compounds (R = Gd, Dy, Ho or Er, R' = Th or Ce)

Magnetic and structural characteristics of the ternary systems Ln.Th Co (Ln = Gd, Dy, Ho and Er) and Ln-Ce Co (Ln = Gd, Dy and 2-x x 17 2-x x 17 Ho) are presented.Incorporation of Th in the lattice stabilizes the Th Zn structure *hereas incorporation of Ce does not; if the binary 2 17 system has the Th Ni structure the incorporation of Ce leaves the 2 17 structure unchanged.The antiferromagnetic Ln-Co coupling 6bserved in the Ln Co systems persists in the ternary alloys.The moment of the 2 17 cobalt sublattice is decreased when more than half of the Ln is replaced by Th, suggesting that the extra electron contributed by Th enters the Co d-band or d-shell.The direction of easy magnetization is in the basal plane for all composition in the Gd, Dy and Ho systems.In Er Th Co the easy direction is along the c-axis for x=0 and .22-x x 17but is in the basal plane for higher thorium contents.