A new ternary titanium(N) arsenate, CsTi2As3O12, has been synthesized
by a flux method and structurally characterized by single-crystal X-ra
y diffraction. It crystallizes in the cubic space group Ia (3) over ba
r d (No. 230) with a = 20.495(3) Angstrom, V = 8609(2) Angstrom(3), Z
= 32, and R = 0.0242. The framework consists of vertex-sharing TiO6 oc
tahedra and AsO4 tetrahedra, enclosing large cavities in which the ces
ium atom sites are partially occupied. The cavities are interconnected
to form 3-dimensional channels. The structure is considerably differe
nt from those of NASICON and langbeinite.