Calculation of ferromagnetic states in metastable bcc and hcp Ni by projector-augmented wave method

Based on a projector-augmented wave method, ab initio calculations reveal that hcp Ni is ferromagnetic with a magnetic moment of 0.59 mu(B), which is slightly smaller than 0.60 mu(B) in the stable fcc Ni. For bcc Ni, it is found that a ferromagnetic is energetically favored when the lattice constant a > 2.69 angstrom, below which there may be a coexisting state of ferromagnetic and nonmagnetic behaviors. Interestingly, although bec Ni has a smallest magnetic moment of 0.55 mu(B), it has a largest average atomic volume among the three structures, differing sharply from the cases of Fe and Co. (c) 2005 American Institute of Physics.