An energetic salt, sodium nitroformate （NaNF）, was synthesized and characterized by elemental analysis, IR and UV spectra, and its crystal structure was first determined by single crystal X-ray diffraction. The stru...An energetic salt, sodium nitroformate （NaNF）, was synthesized and characterized by elemental analysis, IR and UV spectra, and its crystal structure was first determined by single crystal X-ray diffraction. The structure exhibits two types of π-π stacking interactions between the nitroformate anions, i e, the parallel-displaced and T-shaped confgurafions. Furthermore, the thermal decomposition mechanism was investigated by DSC, TG-DTG and FTIR techniques. The kinetic parameters of the thermal decomposition were also calculated by using Kissinger＇s and Ozawa-Doyle＇s methods. The results show that NaNF has a good thermal stability, which is attributed to the π-π stacking interactions.展开更多
The microcosmic reaction mechanism of the thermal decomposition of potassium nitroformate（KNF） has been investigated by density functional theory within the generalized gradient approximation. The geometric structur...The microcosmic reaction mechanism of the thermal decomposition of potassium nitroformate（KNF） has been investigated by density functional theory within the generalized gradient approximation. The geometric structures of reactants, intermediates, transition states, and products are fully optimized. The frequency analysis approves the authenticity of intermediates and transition states. Our results show that there are four feasible reaction pathways. The main pathway of the reaction is KNF → B1 → TSB1 → B2 → TSB2 → B3 → TSB3 → B4 → KNO2 ＋ NO2 ＋ NO ＋ CO, and the energy barrier of the rate-limiting step is 216.30 k J·mol^-1. The dominant products predicted theoretically are KNO2, NO2, NO, and CO, which is in agreement with the experiment.展开更多
为了研究硝仿肼(HNF)的结构和性质,采用密度泛函理论,在优化HNF晶体结构的基础上,计算了HNF的电子结构、弹性性质和光学性质。结果表明,HNF的能隙为1.818 e V;HNF态密度价带部分由各原子轨道共同组成,导带部分由N-2p和O-2p轨道杂化组成;...为了研究硝仿肼(HNF)的结构和性质,采用密度泛函理论,在优化HNF晶体结构的基础上,计算了HNF的电子结构、弹性性质和光学性质。结果表明,HNF的能隙为1.818 e V;HNF态密度价带部分由各原子轨道共同组成,导带部分由N-2p和O-2p轨道杂化组成;HNF离子基团内各原子间均以共价键互相作用,离子基团间通过强离子键相互作用,N—O共价键表现出较强的极性。HNF的弹性常数满足单斜晶系稳定性条件,采用Voigt-Reuss-Hill方法计算得到了体弹模量、剪切模量和杨氏模量;利用能带结构和态密度分析了HNF的介电函数,折射率,吸收和反射光谱等光学性质,其中静态介电常数ε_1(0)=2.14,静态折射率n_0=1.46,消光系数随能量的变化与吸收光谱相符,吸收光谱在能量为4.42 eV时,有最大吸收峰值5.26×104cm^(-1),在能量为4.99 e V时,反射率有最大值0.153。展开更多
基金Funded by the National"973"Projectthe National Natural Science Foundation of China(No.20471008)+1 种基金the Natural Science Foundation of Chongqing(No.cstc2011jjA50013)the Chongqing Municipal Commission of Education(No.KJ111310)
文摘An energetic salt, sodium nitroformate （NaNF）, was synthesized and characterized by elemental analysis, IR and UV spectra, and its crystal structure was first determined by single crystal X-ray diffraction. The structure exhibits two types of π-π stacking interactions between the nitroformate anions, i e, the parallel-displaced and T-shaped confgurafions. Furthermore, the thermal decomposition mechanism was investigated by DSC, TG-DTG and FTIR techniques. The kinetic parameters of the thermal decomposition were also calculated by using Kissinger＇s and Ozawa-Doyle＇s methods. The results show that NaNF has a good thermal stability, which is attributed to the π-π stacking interactions.
基金supported by the Scientific and Technological Research Program of Chongqing Municipal Education Commission(KJ131318,KJ1401227,KJ15012002)the Fuling Science and Technology Commission(FLKJ2015ABA1042)the Project of Chongqing Key Laboratory of Inorganic Special Functional Materials(KFKT201506)
文摘The microcosmic reaction mechanism of the thermal decomposition of potassium nitroformate（KNF） has been investigated by density functional theory within the generalized gradient approximation. The geometric structures of reactants, intermediates, transition states, and products are fully optimized. The frequency analysis approves the authenticity of intermediates and transition states. Our results show that there are four feasible reaction pathways. The main pathway of the reaction is KNF → B1 → TSB1 → B2 → TSB2 → B3 → TSB3 → B4 → KNO2 ＋ NO2 ＋ NO ＋ CO, and the energy barrier of the rate-limiting step is 216.30 k J·mol^-1. The dominant products predicted theoretically are KNO2, NO2, NO, and CO, which is in agreement with the experiment.
文摘为了研究硝仿肼(HNF)的结构和性质,采用密度泛函理论,在优化HNF晶体结构的基础上,计算了HNF的电子结构、弹性性质和光学性质。结果表明,HNF的能隙为1.818 e V;HNF态密度价带部分由各原子轨道共同组成,导带部分由N-2p和O-2p轨道杂化组成;HNF离子基团内各原子间均以共价键互相作用,离子基团间通过强离子键相互作用,N—O共价键表现出较强的极性。HNF的弹性常数满足单斜晶系稳定性条件,采用Voigt-Reuss-Hill方法计算得到了体弹模量、剪切模量和杨氏模量;利用能带结构和态密度分析了HNF的介电函数,折射率,吸收和反射光谱等光学性质,其中静态介电常数ε_1(0)=2.14,静态折射率n_0=1.46,消光系数随能量的变化与吸收光谱相符,吸收光谱在能量为4.42 eV时,有最大吸收峰值5.26×104cm^(-1),在能量为4.99 e V时,反射率有最大值0.153。
