First Heat of Formation Determined from Experimental Standard Molar Enthalpy of Combustion Values for a High Energy Binary Heterocyclium closo-Icosahedral Dodecaborane Salt: [1-Amino-3-H-1,2,3-triazolium]2[closo-B12H12]
Abstract
The first standard molar enthalpy of combustion and resultant heat of formation were determined for a binary heterocyclium closo-icosahedral dodecaborane [B12H12] salt selected from a number of recently synthesized water and air-stable salt analogues that represent a new family of high energy materials. Two heterocyclic 1-amino-3-H-1,2,3-triazolium cations, stoichiometrically paired with the unique [closo-B12H12]2 di-anion, formed a 99.2% pure [1AT3H]2[closo-B12H12] salt that revealed a standard enthalpy of combustion equal to (12675.9 - 3.5) kJ/mol or (3029.6 0.8) kcal/mol. Using the Hess thermochemical cycle, the standard molar heat of formation was determined to be (25.1 - 3.5) kJ/mol or (6.0 - 0.8) kcal/mol. These thermochemical values are significantly higher than those reported for the only other type of closo-borane based salts that paired two acyclium (ammonium, hydrazinium, or guanidinium) cations with the lower di-anion homologue. These [acyclium]2[closo-B10H10] salts required an accelerant compound to promote complete combustion, but the heterocyclic-based [1AT3H]2[closo-B12H12] salt provided the best combustion values as a single entity.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 05, 2010
- Accession Number
- ADA527275
Entities
People
- Brett A. Wight
- John L. Belletire
- Mark E. Henry
- Scott A. Shackelford
- Stefan Schneider
- Steven L. Strauss
Organizations
- Air Force Research Laboratory