ic200990m_si_001.pdf (75.97 kB)
Role of NH3 in the Dehydrogenation of Calcium Amidoborane Ammoniate and Magnesium Amidoborane Ammoniate: A First-Principles Study
journal contributionposted on 2012-01-02, 00:00 authored by Wen Li, Guotao Wu, Yongshen Chua, Yuan Ping Feng, Ping Chen
First-principles calculations show that [NH3] 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(NH2BH3)2·2NH3 or Mg(NH2BH3)2·NH3 occurring at lower temperatures compared to those of Ca(NH2BH3)2 and Mg(NH2BH3)2. Moreover, the calculations of Helmholtz Free energy and [NH3] molecule removal energy evidence that coordination between [NH3] and Mg cation is stronger than that between [NH3] and Ca cation; therefore, Mg(NH2BH3)2·NH3 will undergo directly dehydrogenation rather than deammoniation at lower temperatures.