M-type Gd2[Si2O7]

The title compound, digadolinium(III) oxidodisilicate, Gd 2 [Si 2 O 7 ], was obtained in its M -type crystal structure after attempts to synthesize Gd 5 Br 3 [AsO 3 ] 4 as a by-product from fused silica ampoules. It crystallizes isotypically with M -type Eu 2 [Si 2 O 7 ]. This structure consists of layers of ecliptically arranged oxidodisilicate [Si 2 O 7 ] 6− units separated from each other by bilayers consisting of Gd III cations.