NaCaGaSi2O7 crystallizes in the orthorhombic P2_12_12_1 space group. Na(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(4), one O(6), two equivalent O(5), and two equivalent O(7) atoms. Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(4), one O(7), two equivalent O(3), and two equivalent O(6) atoms. Ga(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form GaO4 tetrahedra that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra and corners with two equivalent Ga(1)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra and corners with two equivalent Ga(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Si(1), and one Si(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Ga(1), and one Si(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Ga(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Ga(1), and one Si(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ga(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Ca(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ca(1), and one Si(1) atom.
NaCaGaSi2O7 crystallizes in the orthorhombic P2_12_12_1 space group. Na(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(4), one O(6), two equivalent O(5), and two equivalent O(7) atoms. The Na(1)-O(1) bond length is 2.54 Å. The Na(1)-O(2) bond length is 2.44 Å. The Na(1)-O(4) bond length is 2.85 Å. The Na(1)-O(6) bond length is 2.83 Å. There is one shorter (2.43 Å) and one longer (2.77 Å) Na(1)-O(5) bond length. There is one shorter (2.50 Å) and one longer (2.73 Å) Na(1)-O(7) bond length. Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(4), one O(7), two equivalent O(3), and two equivalent O(6) atoms. The Ca(1)-O(1) bond length is 2.45 Å. The Ca(1)-O(2) bond length is 2.75 Å. The Ca(1)-O(4) bond length is 2.46 Å. The Ca(1)-O(7) bond length is 2.44 Å. There is one shorter (2.48 Å) and one longer (2.86 Å) Ca(1)-O(3) bond length. There is one shorter (2.50 Å) and one longer (2.62 Å) Ca(1)-O(6) bond length. Ga(1) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form GaO4 tetrahedra that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(2)O4 tetrahedra. The Ga(1)-O(2) bond length is 1.85 Å. The Ga(1)-O(3) bond length is 1.87 Å. The Ga(1)-O(4) bond length is 1.86 Å. The Ga(1)-O(5) bond length is 1.84 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra and corners with two equivalent Ga(1)O4 tetrahedra. The Si(1)-O(1) bond length is 1.67 Å. The Si(1)-O(3) bond length is 1.67 Å. The Si(1)-O(4) bond length is 1.66 Å. The Si(1)-O(7) bond length is 1.59 Å. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra and corners with two equivalent Ga(1)O4 tetrahedra. The Si(2)-O(1) bond length is 1.68 Å. The Si(2)-O(2) bond length is 1.66 Å. The Si(2)-O(5) bond length is 1.65 Å. The Si(2)-O(6) bond length is 1.61 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Si(1), and one Si(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Ga(1), and one Si(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Ga(1), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Na(1), one Ca(1), one Ga(1), and one Si(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ga(1), and one Si(2) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Ca(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ca(1), and one Si(1) atom.