Rb3BaTeB7O15: a novel [B7O16] fundamental building block in a new telluroborate with [TeO3] polyhedra†
A new telluroborate Rb3BaTeB7O15, with a new type of fundamental building block, namely [B7O16] units, has been synthesized by the high-temperature flux method, and it crystallizes in the monoclinic space group P21/n (no. 11) with a three dimensional network. To the best of our knowledge, Rb3BaTeB7O15 is the first telluroborate that is constructed only by using [TeO3] polyhedra. Meanwhile, the stereochemical activity of the [TeO3] polyhedra was demonstrated by employing theoretical calculations. The UV-vis-NIR diffuse reflectance spectrum, thermal gravimetric results, differential scanning calorimetry curves and infrared spectrum of Rb3BaTeB7O15 were characterized and analyzed. In addition, the electronic structures and birefringence were discussed by using the first-principles calculations.