几种新型六氮杂异伍兹烷衍生物结构与性能的理论预测—— 高能量密度化合物的寻求

以CN, NC, ONO2, N3, NH2, N2H, NHNH2, N4H和N4H3 9种含氮高能基团为取代基, 分别取代2,4,6,8,10,12-六氮杂异伍兹烷(IW)中亚氨基的6个H原子所形成的9种六氮杂异伍兹烷衍生物作为研究目标分子. 运用密度泛函理论, 在B3LYP/6-31G**水平上求得了它们的分子几何构型、电子结构、解离能(BDE)及IR谱等信息, 并设计等键反应计算了生成热( ). 基于统计热力学原理计算拟合了100～1200 K温度范围内体系的热力学函数, 利用Kamlet-Jacobs方程估算了它们的爆轰性能. 研究结果表明, 9种六氮杂异伍兹烷衍生物存在两种可能的热解引发类型. 在衍生物HNiIW, HBDAIW和HBAIW中, 可能的热解引发键是取代基内部的化学键, 而其余衍生物的热解引发键则可能是骨架N与取代基R之间N—R键. 另外, 硝酸酯基(ONO2)取代所得化合物HNiIW的密度ρ、爆速D及爆压p分别为1.998 g•cm－3, 9.71 km•s－1和44.47 GPa, 完全达到高能量密度化合物(HEDC)的基本要求, 且优于已应用的HNIW, 有望成为新型的HEDC.

Theoretical Predictions on the Structures and Properties for Several Novel Hexaazaisowurtzitane Derivatives--Looking for H EDC

Nine kinds of novel hexaazaisowurtzitane derivatives were designed in which six hydrogen atoms of the imino groups of 2,4,6,8,10,12-hexaazaisowurtzitane (IW) have been substituted by CN, NC, ONO2, N3, NH2, N2H, NHNH2, N4H and N4H3 groups, respectively. B3LYP/6-31G** level of the density functional theory has been applied to study the optimized molecular geometries, electronic structures, bond dissociation energies (BDE) and IR spectra of the hexaazaisowurtzitane derivatives. And, their heat of formation ( ) was evaluated by using the isodesmic reactions. Their thermodynamic functions in the temperature range of 100～1200 K were calculated on the basis of statistical thermodynamic principles and their detonation performances were predicted by means of the Kamlet-Jacobs equations. The studies show that there are two kinds of trigger bonds in the hexaazaisowurtzitane derivatives. One is possibly the chemical bonds within the substituent groups for HNiIW, HBDAIW and HBAIW, and the other is possibly the N—R bond between skeleton N atom and substituent groups R for other hexaazaisowurtzitane derivatives. In addition, the density (ρ), the predicted detonation velocity (D) and detonation pressure (p) of HNiIW are 1.998 g•cm－3, 9.71 km• s－1 and 44.47 GPa, respectively. Detonation performances of HNiIW fully met to the basic requirement of HEDC and is superior to HNIW. Therefore, HNiIW is worthy recommending as a potential candidate for a high energy density compound.