title: Square-pyramidal/triangular framework oxide: synthesis and structure of PKU-6.
abstract: PKU-6, a new aluminoborate (HAl2B3O8), has been synthesized in a closed system at 400 degrees C. The structure of PKU-6, characterized by using powder and single-crystal X-ray diffraction, consists of AlO5 square-pyramidal chains and B3O7 groups, which are interconnected and form a three-dimensional framework. The 27Al NMR study indicates that the isotropic chemical shift of pyramidal Al is 34.6 ppm with a large quadrupolar coupling constant (CQ=4.2 MHz), mainly due to a nonspherical coordination environment.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Yang
authors.forename: Jing
authors.initials: J
authors.lastname: Ju
authors.forename: Guobao
authors.initials: G
authors.lastname: Li
authors.forename: Fuhui
authors.initials: F
authors.lastname: Liao
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Zou
authors.forename: Feng
authors.initials: F
authors.lastname: Deng
authors.forename: Lei
authors.initials: L
authors.lastname: Chen
authors.forename: Yingxia
authors.initials: Y
authors.lastname: Wang
authors.forename: Jianhua
authors.initials: J
authors.lastname: Lin