Materials Data on La(NiAs)2 by Materials Project
LaNi2As2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. La3+ is bonded in a 8-coordinate geometry to eight As3- atoms. There are four shorter (3.22 Å) and four longer (3.23 Å) La–As bond lengths. There are two inequivalent Ni+1.50+ sites. In the first Ni+1.50+ site, Ni+1.50+ is bonded in a 5-coordinate geometry to five As3- atoms. There are four shorter (2.41 Å) and one longer (2.43 Å) Ni–As bond lengths. In the second Ni+1.50+ site, Ni+1.50+ is bonded to four equivalent As3- atoms to form a mixture of edge and corner-sharing NiAs4 tetrahedra. All Ni–As bond lengths are 2.46 Å. There are two inequivalent As3- sites. In the first As3- site, As3- is bonded in a 9-coordinate geometry to four equivalent La3+ and five Ni+1.50+ atoms. In the second As3- site, As3- is bonded in a 4-coordinate geometry to four equivalent La3+ and four equivalent Ni+1.50+ atoms.