Sr11Ge4N6 crystallizes in the tetragonal P4/nbm space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 5-coordinate geometry to two equivalent Ge(3) and three equivalent N(2) atoms. In the second Sr site, Sr(2) is bonded in a 2-coordinate geometry to two equivalent Ge(2) and two equivalent N(1) atoms. In the third Sr site, Sr(3) is bonded in a 5-coordinate geometry to one N(1) and four equivalent N(2) atoms. In the fourth Sr site, Sr(4) is bonded in a linear geometry to four equivalent Ge(2) and two equivalent N(1) atoms. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a water-like geometry to two equivalent N(2) atoms. In the second Ge site, Ge(2) is bonded to four equivalent Sr(4) and eight equivalent Sr(2) atoms to form distorted GeSr12 cuboctahedra that share corners with four equivalent Ge(2)Sr12 cuboctahedra, faces with four equivalent Ge(2)Sr12 cuboctahedra, and faces with eight equivalent N(1)Sr6 octahedra. In the third Ge site, Ge(3) is bonded in a 8-coordinate geometry to eight equivalent Sr(1) atoms. There are two inequivalent N sites. In the first N site, N(2) is bonded to two equivalent Sr(3), three equivalent Sr(1), and one Ge(1) atom to form distorted NSr5Ge octahedra that share corners with two equivalent N(2)Sr5Ge octahedra, corners with two equivalent N(1)Sr6 octahedra, edges with four equivalent N(2)Sr5Ge octahedra, and  a faceface with one N(2)Sr5Ge octahedra. The corner-sharing octahedral tilt angles range from 32-74°. In the second N site, N(1) is bonded to one Sr(3), one Sr(4), and four equivalent Sr(2) atoms to form NSr6 octahedra that share corners with four equivalent N(2)Sr5Ge octahedra, corners with five equivalent N(1)Sr6 octahedra, and faces with four equivalent Ge(2)Sr12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-74°.
Sr11Ge4N6 crystallizes in the tetragonal P4/nbm space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 5-coordinate geometry to two equivalent Ge(3) and three equivalent N(2) atoms. Both Sr(1)-Ge(3) bond lengths are 3.29 Å. There is one shorter (2.47 Å) and two longer (2.82 Å) Sr(1)-N(2) bond lengths. In the second Sr site, Sr(2) is bonded in a 2-coordinate geometry to two equivalent Ge(2) and two equivalent N(1) atoms. There is one shorter (3.35 Å) and one longer (3.79 Å) Sr(2)-Ge(2) bond length. Both Sr(2)-N(1) bond lengths are 2.62 Å. In the third Sr site, Sr(3) is bonded in a 5-coordinate geometry to one N(1) and four equivalent N(2) atoms. The Sr(3)-N(1) bond length is 2.45 Å. All Sr(3)-N(2) bond lengths are 2.93 Å. In the fourth Sr site, Sr(4) is bonded in a linear geometry to four equivalent Ge(2) and two equivalent N(1) atoms. All Sr(4)-Ge(2) bond lengths are 3.66 Å. Both Sr(4)-N(1) bond lengths are 2.71 Å. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a water-like geometry to two equivalent N(2) atoms. Both Ge(1)-N(2) bond lengths are 1.86 Å. In the second Ge site, Ge(2) is bonded to four equivalent Sr(4) and eight equivalent Sr(2) atoms to form distorted GeSr12 cuboctahedra that share corners with four equivalent Ge(2)Sr12 cuboctahedra, faces with four equivalent Ge(2)Sr12 cuboctahedra, and faces with eight equivalent N(1)Sr6 octahedra. In the third Ge site, Ge(3) is bonded in a 8-coordinate geometry to eight equivalent Sr(1) atoms. There are two inequivalent N sites. In the first N site, N(2) is bonded to two equivalent Sr(3), three equivalent Sr(1), and one Ge(1) atom to form distorted NSr5Ge octahedra that share corners with two equivalent N(2)Sr5Ge octahedra, corners with two equivalent N(1)Sr6 octahedra, edges with four equivalent N(2)Sr5Ge octahedra, and  a faceface with one N(2)Sr5Ge octahedra. The corner-sharing octahedral tilt angles range from 32-74°. In the second N site, N(1) is bonded to one Sr(3), one Sr(4), and four equivalent Sr(2) atoms to form NSr6 octahedra that share corners with four equivalent N(2)Sr5Ge octahedra, corners with five equivalent N(1)Sr6 octahedra, and faces with four equivalent Ge(2)Sr12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-74°.