The lowest-energy structures and properties of neutral nickel clusters Nin（n=31―35） were studied by a combination method of genetic algorithm（GA） searching with a tight-binding potential and the density functional theory（DFT） calculations.Structural candidates obtained from our GA search were further optimized with first-principles calculations.Four typical isomers of lower-energy neutral Nin（n=31―35） clusters were shown,as well as their binding energies per atom（Eb）,second differences in energy and magnetic moment.The medium-sized nickel clusters in a size range from 31 atoms to 35 atoms were found to favor the distorted double-icosahedron-like structures.The fragments composed of the central atoms appear as some small stable clusters.
