Vapor Pressures of the Methylamine-Boranes and Ammonia-Triborane¹

Decomposition of NH3BH3 at sub-ambient pressures: A combined thermogravimetry–differential thermal analysis–mass spectrometry study

“…1). This endothermic peak is likely due to AB sublimation, and is consistent with its measurable vapour pressure (<1 mbar at room temperature) [19,20]. Actually, sublimation of NH 3 BH 3 without decomposition during heating under vacuum is widely reported in literature [21][22][23] and is a method commonly used as a purification procedure to obtain solid AB samples.…”

Materials for hydrogen storage: structure and dynamics of borane ammonia complex

“…6 Alternatively, a value of 97 kJ mol −1 is estimated from the standard heats of formation of AB in solid and gaseous states. 7 Such a large molecular cohesive energy is consistent with the low vapor pressure observed for solid AB, <1 micron at 300 K. 8 These specific dihydrogen bonding interactions are of interest to many research groups in their search for properties that lead to low temperature release of chemisorbed hydrogen. 9 Our goal is to develop better fundamental insight into the effect of dihydrogen bonding on the chemical and physical properties of AB.…”

Control of hydrogen release and uptake in amine borane molecular complexes: thermodynamics of ammonia borane, ammonium borohydride, and the diammoniate of diborane

“…While the heat of vaporization, DH v , for a series of methylamine boranes has been reported, 51 the authors noted that the DH v of AB was too low to be determined. Siddick and Morrison 52 used plane-wave density functional theory to provide an estimate of DH v of about 18.6 kcal mol À1 from the cohesive energy for AB at 0 K; that value is comparable to the DH v for methylamine borane (see Table 1).…”