New ZrB$_2$ polymorphs: First-principles calculations

Two new hypothetical zirconium diboride (ZrB2) polymorphs: (hP6-P63/mmc space group, no.194) and (oP6-Pmmn-space group, no.59), were thoroughly studied under the first-principles density functional theory calculations from the structural, mechanical and thermodynamic properties point of view. As opposed to the known phase (hP3-P6/mmm-space group, no.191) are not brittle. Knowledge about these new phases can be very useful when doping metal borides with zirconium.