Ca3Bi3N5 crystallizes in the triclinic P-1 space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 4-coordinate geometry to one N(1), one N(5), and two equivalent N(3) atoms. In the second Ca site, Ca(2) is bonded in a 5-coordinate geometry to one N(1), two equivalent N(2), and two equivalent N(4) atoms. In the third Ca site, Ca(3) is bonded in a distorted square pyramidal geometry to one N(1), one N(2), one N(3), one N(4), and one N(5) atom. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 4-coordinate geometry to one N(3), one N(4), and two equivalent N(2) atoms. In the second Bi site, Bi(2) is bonded in a distorted trigonal non-coplanar geometry to one N(3), one N(4), and one N(5) atom. In the third Bi site, Bi(3) is bonded in a 3-coordinate geometry to one N(1), one N(2), and one N(5) atom. There are five inequivalent N sites. In the first N site, N(1) is bonded to one Ca(1), one Ca(2), one Ca(3), and one Bi(3) atom to form NCa3Bi tetrahedra that share corners with three equivalent N(5)Ca2Bi2 tetrahedra, corners with three equivalent N(3)Ca3Bi2 trigonal bipyramids, and edges with two equivalent N(2)Ca3Bi3 octahedra. In the second N site, N(2) is bonded to one Ca(3), two equivalent Ca(2), one Bi(3), and two equivalent Bi(1) atoms to form distorted NCa3Bi3 octahedra that share corners with two equivalent N(5)Ca2Bi2 tetrahedra,  a cornercorner with one N(3)Ca3Bi2 trigonal bipyramid, edges with two equivalent N(2)Ca3Bi3 octahedra, edges with two equivalent N(1)Ca3Bi tetrahedra, and  an edgeedge with one N(3)Ca3Bi2 trigonal bipyramid. In the third N site, N(3) is bonded to one Ca(3), two equivalent Ca(1), one Bi(1), and one Bi(2) atom to form distorted NCa3Bi2 trigonal bipyramids that share  a cornercorner with one N(2)Ca3Bi3 octahedra, corners with two equivalent N(5)Ca2Bi2 tetrahedra, corners with three equivalent N(1)Ca3Bi tetrahedra,  an edgeedge with one N(2)Ca3Bi3 octahedra,  an edgeedge with one N(5)Ca2Bi2 tetrahedra, and  an edgeedge with one N(3)Ca3Bi2 trigonal bipyramid. The corner-sharing octahedral tilt angles are 76°. In the fourth N site, N(4) is bonded in a 5-coordinate geometry to one Ca(3), two equivalent Ca(2), one Bi(1), and one Bi(2) atom. In the fifth N site, N(5) is bonded to one Ca(1), one Ca(3), one Bi(2), and one Bi(3) atom to form NCa2Bi2 tetrahedra that share corners with two equivalent N(2)Ca3Bi3 octahedra, corners with three equivalent N(1)Ca3Bi tetrahedra, corners with two equivalent N(3)Ca3Bi2 trigonal bipyramids, and  an edgeedge with one N(3)Ca3Bi2 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 57-73°.
Ca3Bi3N5 crystallizes in the triclinic P-1 space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 4-coordinate geometry to one N(1), one N(5), and two equivalent N(3) atoms. The Ca(1)-N(1) bond length is 2.36 Å. The Ca(1)-N(5) bond length is 2.41 Å. There is one shorter (2.54 Å) and one longer (2.55 Å) Ca(1)-N(3) bond length. In the second Ca site, Ca(2) is bonded in a 5-coordinate geometry to one N(1), two equivalent N(2), and two equivalent N(4) atoms. The Ca(2)-N(1) bond length is 2.38 Å. There is one shorter (2.66 Å) and one longer (2.93 Å) Ca(2)-N(2) bond length. There is one shorter (2.40 Å) and one longer (2.47 Å) Ca(2)-N(4) bond length. In the third Ca site, Ca(3) is bonded in a distorted square pyramidal geometry to one N(1), one N(2), one N(3), one N(4), and one N(5) atom. The Ca(3)-N(1) bond length is 2.46 Å. The Ca(3)-N(2) bond length is 2.51 Å. The Ca(3)-N(3) bond length is 2.56 Å. The Ca(3)-N(4) bond length is 2.51 Å. The Ca(3)-N(5) bond length is 2.43 Å. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 4-coordinate geometry to one N(3), one N(4), and two equivalent N(2) atoms. The Bi(1)-N(3) bond length is 2.34 Å. The Bi(1)-N(4) bond length is 2.71 Å. There is one shorter (2.31 Å) and one longer (2.43 Å) Bi(1)-N(2) bond length. In the second Bi site, Bi(2) is bonded in a distorted trigonal non-coplanar geometry to one N(3), one N(4), and one N(5) atom. The Bi(2)-N(3) bond length is 2.25 Å. The Bi(2)-N(4) bond length is 2.31 Å. The Bi(2)-N(5) bond length is 2.24 Å. In the third Bi site, Bi(3) is bonded in a 3-coordinate geometry to one N(1), one N(2), and one N(5) atom. The Bi(3)-N(1) bond length is 2.16 Å. The Bi(3)-N(2) bond length is 2.42 Å. The Bi(3)-N(5) bond length is 2.28 Å. There are five inequivalent N sites. In the first N site, N(1) is bonded to one Ca(1), one Ca(2), one Ca(3), and one Bi(3) atom to form NCa3Bi tetrahedra that share corners with three equivalent N(5)Ca2Bi2 tetrahedra, corners with three equivalent N(3)Ca3Bi2 trigonal bipyramids, and edges with two equivalent N(2)Ca3Bi3 octahedra. In the second N site, N(2) is bonded to one Ca(3), two equivalent Ca(2), one Bi(3), and two equivalent Bi(1) atoms to form distorted NCa3Bi3 octahedra that share corners with two equivalent N(5)Ca2Bi2 tetrahedra,  a cornercorner with one N(3)Ca3Bi2 trigonal bipyramid, edges with two equivalent N(2)Ca3Bi3 octahedra, edges with two equivalent N(1)Ca3Bi tetrahedra, and  an edgeedge with one N(3)Ca3Bi2 trigonal bipyramid. In the third N site, N(3) is bonded to one Ca(3), two equivalent Ca(1), one Bi(1), and one Bi(2) atom to form distorted NCa3Bi2 trigonal bipyramids that share  a cornercorner with one N(2)Ca3Bi3 octahedra, corners with two equivalent N(5)Ca2Bi2 tetrahedra, corners with three equivalent N(1)Ca3Bi tetrahedra,  an edgeedge with one N(2)Ca3Bi3 octahedra,  an edgeedge with one N(5)Ca2Bi2 tetrahedra, and  an edgeedge with one N(3)Ca3Bi2 trigonal bipyramid. The corner-sharing octahedral tilt angles are 76°. In the fourth N site, N(4) is bonded in a 5-coordinate geometry to one Ca(3), two equivalent Ca(2), one Bi(1), and one Bi(2) atom. In the fifth N site, N(5) is bonded to one Ca(1), one Ca(3), one Bi(2), and one Bi(3) atom to form NCa2Bi2 tetrahedra that share corners with two equivalent N(2)Ca3Bi3 octahedra, corners with three equivalent N(1)Ca3Bi tetrahedra, corners with two equivalent N(3)Ca3Bi2 trigonal bipyramids, and  an edgeedge with one N(3)Ca3Bi2 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 57-73°.