Na2EuGeSe4 crystallizes in the tetragonal I-42m space group. Na(1) is bonded in a 4-coordinate geometry to four equivalent Se(1) atoms. Eu(1) is bonded in a 8-coordinate geometry to eight equivalent Se(1) atoms. Ge(1) is bonded in a tetrahedral geometry to four equivalent Se(1) atoms. Se(1) is bonded in a 4-coordinate geometry to two equivalent Na(1), two equivalent Eu(1), and one Ge(1) atom.
Na2EuGeSe4 crystallizes in the tetragonal I-42m space group. Na(1) is bonded in a 4-coordinate geometry to four equivalent Se(1) atoms. All Na(1)-Se(1) bond lengths are 3.03 Å. Eu(1) is bonded in a 8-coordinate geometry to eight equivalent Se(1) atoms. There are four shorter (3.07 Å) and four longer (3.54 Å) Eu(1)-Se(1) bond lengths. Ge(1) is bonded in a tetrahedral geometry to four equivalent Se(1) atoms. All Ge(1)-Se(1) bond lengths are 2.41 Å. Se(1) is bonded in a 4-coordinate geometry to two equivalent Na(1), two equivalent Eu(1), and one Ge(1) atom.