Na4HgP2 crystallizes in the trigonal R-3m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to four equivalent P(1) atoms to form a mixture of corner and edge-sharing NaP4 tetrahedra. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to three equivalent Hg(1) and three equivalent P(1) atoms. Hg(1) is bonded in a distorted body-centered cubic geometry to six equivalent Na(2) and two equivalent P(1) atoms. P(1) is bonded in a body-centered cubic geometry to three equivalent Na(2), four equivalent Na(1), and one Hg(1) atom.
Na4HgP2 crystallizes in the trigonal R-3m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to four equivalent P(1) atoms to form a mixture of corner and edge-sharing NaP4 tetrahedra. There is one shorter (2.88 Å) and three longer (2.99 Å) Na(1)-P(1) bond lengths. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to three equivalent Hg(1) and three equivalent P(1) atoms. All Na(2)-Hg(1) bond lengths are 3.37 Å. All Na(2)-P(1) bond lengths are 2.94 Å. Hg(1) is bonded in a distorted body-centered cubic geometry to six equivalent Na(2) and two equivalent P(1) atoms. Both Hg(1)-P(1) bond lengths are 2.39 Å. P(1) is bonded in a body-centered cubic geometry to three equivalent Na(2), four equivalent Na(1), and one Hg(1) atom.