NaGa(SiO3)2 is Esseneite structured and crystallizes in the monoclinic C2/c space group. Na(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. Ga(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form GaO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra and edges with two equivalent Ga(1)O6 octahedra. Si(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form SiO4 tetrahedra that share corners with three equivalent Ga(1)O6 octahedra and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-60°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to two equivalent Na(1) and two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Na(1), one Ga(1), and one Si(1) atom. In the third O site, O(3) is bonded to one Na(1), two equivalent Ga(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing ONaGa2Si tetrahedra.
NaGa(SiO3)2 is Esseneite structured and crystallizes in the monoclinic C2/c space group. Na(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. Both Na(1)-O(2) bond lengths are 2.42 Å. Both Na(1)-O(3) bond lengths are 2.41 Å. There are two shorter (2.45 Å) and two longer (2.84 Å) Na(1)-O(1) bond lengths. Ga(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form GaO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra and edges with two equivalent Ga(1)O6 octahedra. Both Ga(1)-O(2) bond lengths are 1.94 Å. There are two shorter (2.01 Å) and two longer (2.12 Å) Ga(1)-O(3) bond lengths. Si(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form SiO4 tetrahedra that share corners with three equivalent Ga(1)O6 octahedra and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-60°. The Si(1)-O(2) bond length is 1.61 Å. The Si(1)-O(3) bond length is 1.66 Å. There is one shorter (1.65 Å) and one longer (1.66 Å) Si(1)-O(1) bond length. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to two equivalent Na(1) and two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Na(1), one Ga(1), and one Si(1) atom. In the third O site, O(3) is bonded to one Na(1), two equivalent Ga(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing ONaGa2Si tetrahedra.