Neutron diffraction study of YFe sub 10 minus x Co sub x Mo sub 2

YFe{sub 10{minus}{ital x}}Co{sub {ital x}}Mo{sub 2}(0 {le} {ital x} {le} 10) compounds were synthesized and studied by x-ray and neutron diffraction. Single phase samples with ThMn{sub 12}-type structure can be formed in the entire range of composition. Magnetic properties were studied at fields up to 70 kOe in the temperature range of 1.5 K to room temperature. X-ray diffraction analyses of aligned powders indicate that the easy magnetization direction is parallel to the {ital c} axis when {ital x}{le}6, and deviates from the {ital c} axis when {ital x}{ge}8. Neutron diffraction experiments show that the molybdenum atoms exhibit a strong preference for occupying the 8{ital i} sites, and cobalt atoms prefer to occupy the 8{ital f} and 8{ital j} sites.