Evidence for proximity ofYFe2Si2to a magnetic quantum critical point

Calculations of the electronic and magnetic properties of the nonmagnetic metallic compound ${\mathrm{YFe}}₂{\mathrm{Si}}₂$ are reported. These predict at the density functional level a magnetic state involving ordering along the $c$ axis. This predicted ground state contrasts with experiment, which does not show magnetic order. The electronic structure is three dimensional, and is similar to that of the unconventional superconductor ${\mathrm{YFe}}₂{\mathrm{Ge}}₂$ as well as that of the high-pressure collapsed tetragonal phase of ${\mathrm{KFe}}₂{\mathrm{As}}₂$, which is also a superconductor. Based on the results in relation to experiment, we infer that properties of ${\mathrm{YFe}}₂{\mathrm{Si}}₂$ are strongly influenced by a nearby antiferromagnetic quantum critical point.