Pb4Si(OCl)4 crystallizes in the monoclinic P2_1/c space group. There are four inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 2-coordinate geometry to one O(1), one O(3), one Cl(2), one Cl(3), and one Cl(5) atom. In the second Pb site, Pb(2) is bonded in a 5-coordinate geometry to one O(2), one O(4), one Cl(3), one Cl(4), and two equivalent Cl(2) atoms. In the third Pb site, Pb(3) is bonded in a 2-coordinate geometry to one O(3), one O(4), one Cl(2), and two equivalent Cl(1) atoms. In the fourth Pb site, Pb(4) is bonded in a 3-coordinate geometry to one O(1), two equivalent O(2), one Cl(2), one Cl(3), and one Cl(5) atom. Si(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 1-coordinate geometry to one Pb(1), one Pb(4), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Pb(2), two equivalent Pb(4), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Pb(1), one Pb(3), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Pb(2), one Pb(3), and one Si(1) atom. There are five inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in an L-shaped geometry to two equivalent Pb(3) atoms. In the second Cl site, Cl(2) is bonded in a 5-coordinate geometry to one Pb(1), one Pb(3), one Pb(4), and two equivalent Pb(2) atoms. In the third Cl site, Cl(3) is bonded in a distorted T-shaped geometry to one Pb(1), one Pb(2), and one Pb(4) atom. In the fourth Cl site, Cl(4) is bonded in a linear geometry to two equivalent Pb(2) atoms. In the fifth Cl site, Cl(5) is bonded in a 4-coordinate geometry to two equivalent Pb(1) and two equivalent Pb(4) atoms.
Pb4Si(OCl)4 crystallizes in the monoclinic P2_1/c space group. There are four inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 2-coordinate geometry to one O(1), one O(3), one Cl(2), one Cl(3), and one Cl(5) atom. The Pb(1)-O(1) bond length is 2.34 Å. The Pb(1)-O(3) bond length is 2.38 Å. The Pb(1)-Cl(2) bond length is 3.19 Å. The Pb(1)-Cl(3) bond length is 2.84 Å. The Pb(1)-Cl(5) bond length is 3.27 Å. In the second Pb site, Pb(2) is bonded in a 5-coordinate geometry to one O(2), one O(4), one Cl(3), one Cl(4), and two equivalent Cl(2) atoms. The Pb(2)-O(2) bond length is 2.56 Å. The Pb(2)-O(4) bond length is 2.41 Å. The Pb(2)-Cl(3) bond length is 3.13 Å. The Pb(2)-Cl(4) bond length is 2.90 Å. There is one shorter (3.06 Å) and one longer (3.29 Å) Pb(2)-Cl(2) bond length. In the third Pb site, Pb(3) is bonded in a 2-coordinate geometry to one O(3), one O(4), one Cl(2), and two equivalent Cl(1) atoms. The Pb(3)-O(3) bond length is 2.33 Å. The Pb(3)-O(4) bond length is 2.30 Å. The Pb(3)-Cl(2) bond length is 3.18 Å. There is one shorter (2.93 Å) and one longer (2.97 Å) Pb(3)-Cl(1) bond length. In the fourth Pb site, Pb(4) is bonded in a 3-coordinate geometry to one O(1), two equivalent O(2), one Cl(2), one Cl(3), and one Cl(5) atom. The Pb(4)-O(1) bond length is 2.59 Å. There is one shorter (2.52 Å) and one longer (2.55 Å) Pb(4)-O(2) bond length. The Pb(4)-Cl(2) bond length is 3.05 Å. The Pb(4)-Cl(3) bond length is 3.08 Å. The Pb(4)-Cl(5) bond length is 3.22 Å. Si(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. The Si(1)-O(1) bond length is 1.65 Å. The Si(1)-O(2) bond length is 1.66 Å. The Si(1)-O(3) bond length is 1.65 Å. The Si(1)-O(4) bond length is 1.65 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 1-coordinate geometry to one Pb(1), one Pb(4), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Pb(2), two equivalent Pb(4), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Pb(1), one Pb(3), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Pb(2), one Pb(3), and one Si(1) atom. There are five inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in an L-shaped geometry to two equivalent Pb(3) atoms. In the second Cl site, Cl(2) is bonded in a 5-coordinate geometry to one Pb(1), one Pb(3), one Pb(4), and two equivalent Pb(2) atoms. In the third Cl site, Cl(3) is bonded in a distorted T-shaped geometry to one Pb(1), one Pb(2), and one Pb(4) atom. In the fourth Cl site, Cl(4) is bonded in a linear geometry to two equivalent Pb(2) atoms. In the fifth Cl site, Cl(5) is bonded in a 4-coordinate geometry to two equivalent Pb(1) and two equivalent Pb(4) atoms.