Sr2LaCl7 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one Cl(1), one Cl(2), one Cl(3), one Cl(4), one Cl(5), one Cl(6), and one Cl(7) atom to form distorted SrCl7 pentagonal bipyramids that share corners with five equivalent La(1)Cl7 pentagonal bipyramids and  an edgeedge with one La(1)Cl7 pentagonal bipyramid. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one Cl(1), one Cl(2), one Cl(3), one Cl(4), one Cl(5), one Cl(6), and one Cl(7) atom. La(1) is bonded to one Cl(1), one Cl(2), one Cl(3), one Cl(4), one Cl(5), one Cl(6), and one Cl(7) atom to form distorted LaCl7 pentagonal bipyramids that share corners with five equivalent Sr(1)Cl7 pentagonal bipyramids and  an edgeedge with one Sr(1)Cl7 pentagonal bipyramid. There are seven inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a distorted T-shaped geometry to one Sr(1), one Sr(2), and one La(1) atom. In the second Cl site, Cl(2) is bonded in a trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the third Cl site, Cl(3) is bonded in a trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the fourth Cl site, Cl(4) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the fifth Cl site, Cl(5) is bonded in a distorted trigonal planar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the sixth Cl site, Cl(6) is bonded in a T-shaped geometry to one Sr(1), one Sr(2), and one La(1) atom. In the seventh Cl site, Cl(7) is bonded in a distorted T-shaped geometry to one Sr(1), one Sr(2), and one La(1) atom.
Sr2LaCl7 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one Cl(1), one Cl(2), one Cl(3), one Cl(4), one Cl(5), one Cl(6), and one Cl(7) atom to form distorted SrCl7 pentagonal bipyramids that share corners with five equivalent La(1)Cl7 pentagonal bipyramids and  an edgeedge with one La(1)Cl7 pentagonal bipyramid. The Sr(1)-Cl(1) bond length is 3.00 Å. The Sr(1)-Cl(2) bond length is 2.94 Å. The Sr(1)-Cl(3) bond length is 2.94 Å. The Sr(1)-Cl(4) bond length is 2.95 Å. The Sr(1)-Cl(5) bond length is 3.01 Å. The Sr(1)-Cl(6) bond length is 2.99 Å. The Sr(1)-Cl(7) bond length is 3.03 Å. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one Cl(1), one Cl(2), one Cl(3), one Cl(4), one Cl(5), one Cl(6), and one Cl(7) atom. The Sr(2)-Cl(1) bond length is 3.14 Å. The Sr(2)-Cl(2) bond length is 2.87 Å. The Sr(2)-Cl(3) bond length is 2.97 Å. The Sr(2)-Cl(4) bond length is 2.98 Å. The Sr(2)-Cl(5) bond length is 3.06 Å. The Sr(2)-Cl(6) bond length is 2.95 Å. The Sr(2)-Cl(7) bond length is 2.94 Å. La(1) is bonded to one Cl(1), one Cl(2), one Cl(3), one Cl(4), one Cl(5), one Cl(6), and one Cl(7) atom to form distorted LaCl7 pentagonal bipyramids that share corners with five equivalent Sr(1)Cl7 pentagonal bipyramids and  an edgeedge with one Sr(1)Cl7 pentagonal bipyramid. The La(1)-Cl(1) bond length is 2.86 Å. The La(1)-Cl(2) bond length is 2.87 Å. The La(1)-Cl(3) bond length is 3.04 Å. The La(1)-Cl(4) bond length is 2.85 Å. The La(1)-Cl(5) bond length is 2.98 Å. The La(1)-Cl(6) bond length is 2.84 Å. The La(1)-Cl(7) bond length is 2.88 Å. There are seven inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a distorted T-shaped geometry to one Sr(1), one Sr(2), and one La(1) atom. In the second Cl site, Cl(2) is bonded in a trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the third Cl site, Cl(3) is bonded in a trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the fourth Cl site, Cl(4) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the fifth Cl site, Cl(5) is bonded in a distorted trigonal planar geometry to one Sr(1), one Sr(2), and one La(1) atom. In the sixth Cl site, Cl(6) is bonded in a T-shaped geometry to one Sr(1), one Sr(2), and one La(1) atom. In the seventh Cl site, Cl(7) is bonded in a distorted T-shaped geometry to one Sr(1), one Sr(2), and one La(1) atom.