Local spin-density theory of spin-glasses

We present ab-initio calculations of the spin-structures for the 'spin-glass' alloys Cu95Mn5 and Cu90Mn10, based on the local spin-density approximation (LSDA) and a supercell-approach. The calculations are performed using the linear-muffin-tin-orbital (LMTO) technique with collinear spins as well as a tight-binding-LMTO technique allowing for arbitrary orientations of the local spin-quantization axes. Our calculations predict a spin-glass-like magnetic ground-state, arising from a competition of predominantly antiferromagnetic nearest-neighbour interactions with a ferromagnetic coupling to the more distant neighbours.