title: Theoretical study of the decomposition mechanisms and kinetics of the ingredients RDX in composition B.
abstract: RDX as a component in composition B (TNT + RDX) was first studied by us on its mechanism and kinetics of decomposition reactions in this paper. We have pointed out three possible pathways and found a new low-energy process of its decomposition. The N-N bond cleavage in composition B has higher dissociation energies than the monomer, but it is also the initial step. The optimized structures and the frequencies of all the stationary points were calculated at the B3LYP/6-31G(d) level. The minimum-energy paths were obtained by using the intrinsic reaction coordinate (IRC) theory, and the reaction potential energy curve was corrected with zero-point energy. Finally, the rate constants were calculated in a wide temperature region from 200 to 2500 K using TST, TST/Eckart theories. The obtained results also indicate that the tunneling effects are remarkable at low temperature (200 K <T < 500 K).
authors.affiliation: State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing, 100081, People's Republic of China. zhangjianguobit@yahoo.com.cn
authors.forename: Jian-Guo
authors.initials: JG
authors.lastname: Zhang
authors.forename: Kun
authors.initials: K
authors.lastname: Wang
authors.forename: Xiao-Qing
authors.initials: XQ
authors.lastname: Niu
authors.forename: Shao-Wen
authors.initials: SW
authors.lastname: Zhang
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Feng
authors.forename: Tong-Lai
authors.initials: TL
authors.lastname: Zhang
authors.forename: Zun-Ning
authors.initials: ZN
authors.lastname: Zhou
mesh_terms: D003198:Computer Simulation; D053834:Explosive Agents / Q000737:chemistry*; D007700:Kinetics; D008956:Models, Chemical; D008958:Models, Molecular; D009602:Nitrosamines / Q000737:chemistry*; D011789:Quantum Theory; D013816:Thermodynamics; D014303:Trinitrotoluene / Q000737:chemistry*
chemical_list: D053834:Explosive Agents; D009602:Nitrosamines; D014303:Trinitrotoluene; C014233:trinitrosotrimethylenetriamine