The title compound, dicerium(III) oxidodisilicate, Ce2[Si2O7], was obtained as a by-product in its H-type structure after attempts to synthesize CeSb2O4Cl from fused silica ampoules. It crystallizes isotypically with H-La2[Si2O7]. The four crystallographically distinct CeIII cations form distorted square anti-prisms, capped square anti-prisms, and bicapped square anti-prisms as coordination polyhedra consisting of oxygen atoms. Four crystallographically different silicon atoms recruit the centers of two different isolated [Si2O7]6- units.
Keywords: cerium; crystal structure; isotypism; oxidodisilicate; rare-earth metal.
© Locke et al. 2023.