title: Role of NH3 in the dehydrogenation of calcium amidoborane ammoniate and magnesium amidoborane ammoniate: a first-principles study.
abstract: First-principles calculations show that [NH(3)] molecules play crucial roles as both activator for the break-up of B-H bond and supplier of protic H for the establishment of dihydrogen bonding, which could facilitate the dehydrogenation of Ca(NH(2)BH(3))(2)·2NH(3) or Mg(NH(2)BH(3))(2)·NH(3) occurring at lower temperatures compared to those of Ca(NH(2)BH(3))(2) and Mg(NH(2)BH(3))(2). Moreover, the calculations of Helmholtz Free energy and [NH(3)] molecule removal energy evidence that coordination between [NH(3)] and Mg cation is stronger than that between [NH(3)] and Ca cation; therefore, Mg(NH(2)BH(3))(2)·NH(3) will undergo directly dehydrogenation rather than deammoniation at lower temperatures.
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P.R. China.
authors.forename: Wen
authors.initials: W
authors.lastname: Li
authors.forename: Guotao
authors.initials: G
authors.lastname: Wu
authors.forename: Yongshen
authors.initials: Y
authors.lastname: Chua
authors.forename: Yuan Ping
authors.initials: YP
authors.lastname: Feng
authors.forename: Ping
authors.initials: P
authors.lastname: Chen