Abstract: | CuTbB5O10]: The first “Metaborate” with a B5O10]5? Anion Single crystals of the new compound CuTbB5O10] were obtained by a B2O3 flux-technique. They crystallize in a so far unknown structure. X-ray investigations on single crystals led to the space group C –I ba2 (Nr. 45); a = 6.294(1) Å; b = 8.406(8) Å; c = 12.733(2) Å; Z = 4. The structure contains B5O10]5? chains isolated from each other. These chains include twelf membered rings of boron and oxygen. Each ring consists of two tetrahedral BO4 and two planar B2O5 groups and is connected with the next one via the BO4 units. Tb3+ is eightfold- and Cu2+ elongated octahedraly coordinated by oxygen. |