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近来,人们在越来越多地进行碳笼烯的理论研究的同时,开始预测是否有同样几何结构的氮笼,1980年Volger在实验上就得到γ=380nm的N_6分子,许多理论研究已经涉及到氮笼分子,其中Bliznyuk等人在HF水平下计算了I_h对称性下的N_(20)分子的几何结构,指出N_(20)是一种子metastable分子,在N_(20)分子中的每摩尔N原子能量比10个N_2分子中的每摩尔N原子能量多出2.09×10~5J/mol,认为如果能合成出N_(20)分子,它将是一种潜在的高能量密度材料。在Leininger等人的文章中,比较了N_8的3种异构体与N_(20)和另外一类高能量密度材料O_n的分解能,指出在MP2水平下N_8分解为N_2时的分解能(每摩尔原子)比O_n分解为O_2的分解能高出2～3倍,说明N_8也是一种潜在的高能量密度材料,同时也指出由于N_8(O_h)的高势能,合成它采用普通的化学方法是行不通的,或许可以采用光化学反应,如由开链的D_(2d)对称性的N_8分子在光作用下进行[2+2]环加成反应得到。
Recently, more and more studies on the theory of C-Clay began to predict the existence of the same geometry of the nitrogen cage. In 1980, Volger experimented to obtain γ = 380nm of N_6 molecules. Many theoretical studies have been involved To the nitrogen cage molecule, Bliznyuk et al. Calculated the geometry of the N20 molecule under I_h symmetry and pointed out that N_ (20) is a sub-metastable molecule with a molecular weight per mole The N atom energy is 2.09 × 10 ~ 5 J / mol more than the energy per N atom in 10 N 2 molecules, and it is considered that if the N 20 molecule can be synthesized, it will be a potentially high energy density material. In Leininger et al., The decomposition energies of three isomers of N_8, N_ (20) and another high energy density material, O_n, were compared. The decomposition energies of N_8 to N_2 at MP2 ) Is 2 ~ 3 times higher than the decomposition of O_n to O_2, indicating that N_8 is also a potential high energy density material. It is also pointed out that it is not feasible to synthesize it by ordinary chemical methods due to the high potential energy of N_8 (O_h) , Perhaps photochemical reaction can be used, such as by the open chain D_ (2d) symmetry of N_8 molecules under the action of light [2 + 2] cycloaddition obtained.