Ca3Ga5 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 9-coordinate geometry to two equivalent Ga(3), three equivalent Ga(1), and four equivalent Ga(2) atoms. In the second Ca site, Ca(2) is bonded in a 11-coordinate geometry to two equivalent Ga(1), four equivalent Ga(2), and five equivalent Ga(3) atoms. There are three inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 9-coordinate geometry to three equivalent Ca(1), four equivalent Ca(2), and two equivalent Ga(2) atoms. In the second Ga site, Ga(2) is bonded in a 10-coordinate geometry to two equivalent Ca(1), four equivalent Ca(2), one Ga(1), and three equivalent Ga(3) atoms. In the third Ga site, Ga(3) is bonded in a 10-coordinate geometry to one Ca(1), five equivalent Ca(2), one Ga(3), and three equivalent Ga(2) atoms.
Ca3Ga5 crystallizes in the orthorhombic Cmcm space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 9-coordinate geometry to two equivalent Ga(3), three equivalent Ga(1), and four equivalent Ga(2) atoms. Both Ca(1)-Ga(3) bond lengths are 3.24 Å. There are two shorter (3.13 Å) and one longer (3.14 Å) Ca(1)-Ga(1) bond length. All Ca(1)-Ga(2) bond lengths are 3.27 Å. In the second Ca site, Ca(2) is bonded in a 11-coordinate geometry to two equivalent Ga(1), four equivalent Ga(2), and five equivalent Ga(3) atoms. Both Ca(2)-Ga(1) bond lengths are 3.16 Å. There are a spread of Ca(2)-Ga(2) bond distances ranging from 3.10-3.37 Å. There are a spread of Ca(2)-Ga(3) bond distances ranging from 3.10-3.34 Å. There are three inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 9-coordinate geometry to three equivalent Ca(1), four equivalent Ca(2), and two equivalent Ga(2) atoms. Both Ga(1)-Ga(2) bond lengths are 2.63 Å. In the second Ga site, Ga(2) is bonded in a 10-coordinate geometry to two equivalent Ca(1), four equivalent Ca(2), one Ga(1), and three equivalent Ga(3) atoms. There are two shorter (2.62 Å) and one longer (2.75 Å) Ga(2)-Ga(3) bond length. In the third Ga site, Ga(3) is bonded in a 10-coordinate geometry to one Ca(1), five equivalent Ca(2), one Ga(3), and three equivalent Ga(2) atoms. The Ga(3)-Ga(3) bond length is 2.68 Å.