A new compound, Pb6AlB2O7F7, was synthesized from the PbF2/B2O3 flux system, which is the first compound found in the PbF2/Al2O3/B2O3 system. It crystallizes in the orthorhombic system, space group Cmca (No. 64) with unit cell parameters a = 11.649(7) angstrom, b = 18.300(11) angstrom, c = 6.394(4) angstrom, Z = 4. The crystal structure of Pb6AlB2O7F7 contains the group Pb6BO11F10 as basal building unit, which connects with each other forming two-dimensional (infinity)Pb6BO11F10 layers, whereas aluminum atoms are filled in the interlayers. The IR spectrum further confirms the presence of BO3 groups. The calculated band structures and the density of states of Pb6AlB2O7F7 suggest that its indirect gap is 2.968 eV. The DSC analysis and X-ray diffraction technique prove that Pb6AlB2O7F7 is a congruent-melting compound.
Chinese Acad Sci, Xinjiang Tech Inst Phys & Chem, Xinjiang Key Lab Elect Informat Mat & Devices, Urumqi 830011, Peoples R China;Chinese Acad Sci, Grad Sch, Beijing 100049, Peoples R China;Yili Normal Univ, Xinjiang Lab Phase Transit & Microstruct Condense, Yining 835000, Xinjiang, Peoples R China
Dong Lingyun,Pan Shilie,Yang Zhihua,et al. Synthesis, Crystal Structure, and Properties of a New Lead Aluminum Fluoride Borate, Pb6AlB2O7F7[J]. ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE,2012,638(14):2280-2285.