TcB4 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Tc sites. In the first Tc site, Tc(1) is bonded in a 14-coordinate geometry to two equivalent B(2) and twelve equivalent B(1) atoms. In the second Tc site, Tc(2) is bonded to twelve equivalent B(1) atoms to form face-sharing TcB12 cuboctahedra. There are two inequivalent B sites. In the first B site, B(2) is bonded in a 8-coordinate geometry to one Tc(1), one B(2), and six equivalent B(1) atoms. In the second B site, B(1) is bonded in a 9-coordinate geometry to two equivalent Tc(1), two equivalent Tc(2), two equivalent B(2), and three equivalent B(1) atoms.
TcB4 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Tc sites. In the first Tc site, Tc(1) is bonded in a 14-coordinate geometry to two equivalent B(2) and twelve equivalent B(1) atoms. Both Tc(1)-B(2) bond lengths are 2.41 Å. All Tc(1)-B(1) bond lengths are 2.39 Å. In the second Tc site, Tc(2) is bonded to twelve equivalent B(1) atoms to form face-sharing TcB12 cuboctahedra. All Tc(2)-B(1) bond lengths are 2.41 Å. There are two inequivalent B sites. In the first B site, B(2) is bonded in a 8-coordinate geometry to one Tc(1), one B(2), and six equivalent B(1) atoms. The B(2)-B(2) bond length is 1.70 Å. All B(2)-B(1) bond lengths are 1.92 Å. In the second B site, B(1) is bonded in a 9-coordinate geometry to two equivalent Tc(1), two equivalent Tc(2), two equivalent B(2), and three equivalent B(1) atoms. There is one shorter (1.74 Å) and two longer (1.77 Å) B(1)-B(1) bond lengths.