Mn4N2Se3 crystallizes in the orthorhombic Pnnm space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 4-coordinate geometry to two equivalent N(1) and two equivalent Se(1) atoms. In the second Mn site, Mn(2) is bonded in a 5-coordinate geometry to two equivalent N(1) and three equivalent Se(2) atoms. N(1) is bonded to two equivalent Mn(1) and two equivalent Mn(2) atoms to form a mixture of corner and edge-sharing NMn4 trigonal pyramids. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a square co-planar geometry to four equivalent Mn(1) atoms. In the second Se site, Se(2) is bonded in a distorted trigonal planar geometry to three equivalent Mn(2) atoms.
Mn4N2Se3 crystallizes in the orthorhombic Pnnm space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 4-coordinate geometry to two equivalent N(1) and two equivalent Se(1) atoms. There is one shorter (1.87 Å) and one longer (1.91 Å) Mn(1)-N(1) bond length. Both Mn(1)-Se(1) bond lengths are 2.47 Å. In the second Mn site, Mn(2) is bonded in a 5-coordinate geometry to two equivalent N(1) and three equivalent Se(2) atoms. Both Mn(2)-N(1) bond lengths are 1.93 Å. All Mn(2)-Se(2) bond lengths are 2.51 Å. N(1) is bonded to two equivalent Mn(1) and two equivalent Mn(2) atoms to form a mixture of corner and edge-sharing NMn4 trigonal pyramids. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a square co-planar geometry to four equivalent Mn(1) atoms. In the second Se site, Se(2) is bonded in a distorted trigonal planar geometry to three equivalent Mn(2) atoms.