二元含能富氮化合物PN_(3)的理论研究

Theoretical Investigations on a Binary Energetic Nitrogen-rich Compound PN_(3)

为寻找高能量和动力学性能优异的潜在含能分子,采用量子化学方法在CCSD(T)/aug?cc?pVTZ//M06?2X/6?31+G(d,p)水平下构建了磷原子掺杂的富氮化合物PN_3的单重态与三重态势能面,共确认了13种异构体和21个与之相关联的过渡态。对比这些异构体的总能量发现,三态链状异构体~3PNNN(C_s)是热力学最稳定的结构,四面体形异构体~1PN_3(C_(3v))的解离能垒为231.39 kJ·mol^(-1),为了进一步验证异构体的动力学稳定性,在B3LYP/6?31+G(d)水平下对~3PNNN(C_s)和~1PN_3(C_(3v))结构进行了波恩?奥本海默分子动力学(BOMD)模拟,结果表明两个异构体在35 ps内均未发生解离和异构化等变化,具有较好的动力学稳定性。

To explore promising energetic molecular species with huge energy release and significant kinetic stability,the singlet and triplet potential energy surface of nitrogen-rich compound PN3 were constructed at the CCSD(T)/aug-cc-pVTZ//M06-2X/ 6?31+G(d,p)level.The computations performed identified 13 isomers and 21 transition states. The ground state isomer was the chain-like triplet PNNN(Cs). The kinetic stability of PN3 was further evaluated by studying the dissociation,isomerization as well as the Born-Oppenheimer molecular dynamic(BOMD)simulations at the B3LYP/6?31+G(d)level. The results indicated that the chain-like triplet PNNN(Cs )and the tetrahedral-like singlet PN(3 C3v )are both kinetically stable.