MgCr4(PbO4)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(6) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a tetrahedral geometry to one O(1), one O(3), one O(6), and one O(8) atom. In the second Cr site, Cr(2) is bonded in a tetrahedral geometry to one O(2), one O(4), one O(5), and one O(7) atom. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 5-coordinate geometry to one O(2), one O(6), one O(7), and two equivalent O(3) atoms. In the second Pb site, Pb(2) is bonded in a 4-coordinate geometry to one O(5), one O(8), and two equivalent O(4) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded in an L-shaped geometry to one Mg(1) and one Cr(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Cr(2) and one Pb(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cr(1) and two equivalent Pb(1) atoms. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Cr(2) and two equivalent Pb(2) atoms. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Cr(2) and one Pb(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(1), and one Pb(1) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Cr(2) and one Pb(1) atom. In the eighth O site, O(8) is bonded in a 1-coordinate geometry to one Cr(1) and one Pb(2) atom.
MgCr4(PbO4)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(6) atoms. Both Mg(1)-O(1) bond lengths are 2.03 Å. Both Mg(1)-O(6) bond lengths are 2.02 Å. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a tetrahedral geometry to one O(1), one O(3), one O(6), and one O(8) atom. The Cr(1)-O(1) bond length is 1.75 Å. The Cr(1)-O(3) bond length is 1.70 Å. The Cr(1)-O(6) bond length is 1.77 Å. The Cr(1)-O(8) bond length is 1.70 Å. In the second Cr site, Cr(2) is bonded in a tetrahedral geometry to one O(2), one O(4), one O(5), and one O(7) atom. The Cr(2)-O(2) bond length is 1.65 Å. The Cr(2)-O(4) bond length is 1.69 Å. The Cr(2)-O(5) bond length is 1.67 Å. The Cr(2)-O(7) bond length is 1.68 Å. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 5-coordinate geometry to one O(2), one O(6), one O(7), and two equivalent O(3) atoms. The Pb(1)-O(2) bond length is 2.73 Å. The Pb(1)-O(6) bond length is 2.54 Å. The Pb(1)-O(7) bond length is 2.52 Å. There is one shorter (2.40 Å) and one longer (2.60 Å) Pb(1)-O(3) bond length. In the second Pb site, Pb(2) is bonded in a 4-coordinate geometry to one O(5), one O(8), and two equivalent O(4) atoms. The Pb(2)-O(5) bond length is 2.46 Å. The Pb(2)-O(8) bond length is 2.36 Å. There is one shorter (2.48 Å) and one longer (2.69 Å) Pb(2)-O(4) bond length. There are eight inequivalent O sites. In the first O site, O(1) is bonded in an L-shaped geometry to one Mg(1) and one Cr(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Cr(2) and one Pb(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cr(1) and two equivalent Pb(1) atoms. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Cr(2) and two equivalent Pb(2) atoms. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Cr(2) and one Pb(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Cr(1), and one Pb(1) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Cr(2) and one Pb(1) atom. In the eighth O site, O(8) is bonded in a 1-coordinate geometry to one Cr(1) and one Pb(2) atom.