Synthesis, Structure and Properties of Compounds Derived from Kotoite‐related Structures: A2MB2O6 (A=Zn, Ba, Pb; B=Pb, Ba, Zn, Cu)

A series of compounds with the general formula A2MB2O6 (A=Zn, Ba, Pb; B=Pb, Ba, Zn, Cu) related to the kotoite structure has been prepared employing high‐temperature solid state methods. The substitution of transition elements in place of Zn2+ ions resulted in colored compounds. The optical absorption spectra could be explained based on Tanabe‐Sugano diagram and allowed d‐d transitions. Dielectric studies on Ba2ZnB2O6, (Ba1.5Pb0.5)ZnB2O6, PbZn2B2O6, Pb1.5Zn1.5B2O6, BaZn2B2O6 and Pb2CuB2O6 at room temperature indicate reasonable values at low frequencies, which decrease on increasing frequencies. Magnetic study of synthesized single‐phase compounds BaZnCoB2O6 and Pb2CuB2O6 have been performed. The substitution of Eu3+, Tb3+ and Tm3+ in place of Ba2+ in Ba2ZnB2O6, gives rise to the expected emission of red, green and blue colors. Suitable modifications of the different phosphors in Ba2ZnB2O6, resulted in white‐light emission in Ba2ZnB2O6. The Pb2CuB2O6 compound was found to be a good catalyst in the ipso‐hydroxylation of arylboronic acids. [ABSTRACT FROM AUTHOR]