title: Synthesis and crystal structure of Sr(2)AlH(7): a new structural type of alkaline earth aluminum hydride.
abstract: The title hydride and its deuteride were successfully synthesized. The heavy atom structure and hydrogen positions were determined respectively by X-ray powder diffraction and time-of-flight neutron powder diffraction. They crystallize with a new monoclinic structure in space group I2 (No. 5); cell parameters: a = 12.575(1) A, b = 9.799(1) A, c = 7.9911(8) A, beta = 100.270(4) degrees (hydride), a = 12.552(1) A, b = 9.7826(8) A, c = 7.9816(7) A, beta = 100.286(4) degrees (deuteride), Z = 8. Sr(2)AlH(7) is the first example that consists of isolated [AlH(6)] units and infinite one-dimensional twisted chains of edge-sharing [HSr(4)] tetrahedra along the crystallographic c axis.
authors.affiliation: National Institute of Advanced Industrial Science and Technology, AIST Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan.
authors.forename: Qing-An
authors.initials: QA
authors.lastname: Zhang
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Ken-ich
authors.initials: KI
authors.lastname: Oikawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Kamiyama
authors.forename: Etsuo
authors.initials: E
authors.lastname: Akiba