GdB4 crystallizes in the tetragonal P4/mbm space group. Gd(1) is bonded in a 18-coordinate geometry to four equivalent B(1), six equivalent B(3), and eight equivalent B(2) atoms. There are three inequivalent B sites. In the first B site, B(2) is bonded in a 9-coordinate geometry to four equivalent Gd(1), one B(3), two equivalent B(1), and two equivalent B(2) atoms. In the second B site, B(1) is bonded in a 9-coordinate geometry to four equivalent Gd(1), one B(1), and four equivalent B(2) atoms. In the third B site, B(3) is bonded in a distorted trigonal planar geometry to six equivalent Gd(1), one B(3), and two equivalent B(2) atoms.
GdB4 crystallizes in the tetragonal P4/mbm space group. Gd(1) is bonded in a 18-coordinate geometry to four equivalent B(1), six equivalent B(3), and eight equivalent B(2) atoms. All Gd(1)-B(1) bond lengths are 2.74 Å. There are four shorter (2.88 Å) and two longer (3.08 Å) Gd(1)-B(3) bond lengths. There are four shorter (2.76 Å) and four longer (2.84 Å) Gd(1)-B(2) bond lengths. There are three inequivalent B sites. In the first B site, B(2) is bonded in a 9-coordinate geometry to four equivalent Gd(1), one B(3), two equivalent B(1), and two equivalent B(2) atoms. The B(2)-B(3) bond length is 1.73 Å. Both B(2)-B(1) bond lengths are 1.76 Å. Both B(2)-B(2) bond lengths are 1.81 Å. In the second B site, B(1) is bonded in a 9-coordinate geometry to four equivalent Gd(1), one B(1), and four equivalent B(2) atoms. The B(1)-B(1) bond length is 1.65 Å. In the third B site, B(3) is bonded in a distorted trigonal planar geometry to six equivalent Gd(1), one B(3), and two equivalent B(2) atoms. The B(3)-B(3) bond length is 1.77 Å.