Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1811082 | Physica B: Condensed Matter | 2012 | 5 Pages |
The structural, elastic, magnetic and electronic properties of the layered tetragonal phase KCo2Se2 have been examined in details by means of the first-principles calculations and analyzed in comparison with the isostructural KFe2Se2 as the parent phase for the newest group of ternary superconducting iron-chalcogenide materials. Our data show that KCo2Se2 should be characterized as a quasi-two-dimensional ferromagnetic metal with highly anisotropic inter-atomic bonding owing to mixed ionic, covalent, and metallic contributions inside [Co2Se2] blocks, and with ionic bonding between the adjacent [Co2Se2] blocks and K sheets. This material should behave in a brittle manner, adopt enhanced elastic anisotropy rather in compressibility than in shear, and should show very low hardness.