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用ａｂｉｎｉｔｉｏＭＯ方法，在ＭＰ２（ｆｕｌ）／６３１１Ｇ水平下，全优化计算了叠氮化钠（ＮａＮ３）分子的线状和环状两种稳定构型及其转化过渡态的几何参数、电荷分布、分子总能量和振动频率，并研究了它们的热力学性质及转化速率常数和平衡常数．结果表明，线状比环状构型稍稳定（能量低６．０４ｋＪ／ｍｏｌ）；两者相互转化的能垒分别为１３．１５ｋＪ／ｍｏｌ（线型→环状）和７．１１ｋＪ／ｍｏｌ（环状→线型）．热力学和动力学计算均表明：ＮａＮ３通常主要以线型结构存在（占８５％以上），且随温度升高而增多（在１０００Ｋ大于９１％）．
Using abinitioMO method, we calculated the linear and cyclic stable structures of sodium azide (NaN3) and their geometrical parameters of the transition transition state under the level of MP2 (ful) / 6-311G. The charge Distribution, total energy of molecules and frequency of vibration, and studied their thermodynamic properties and conversion rate constants and equilibrium constants. The results show that the linear shape is slightly stabler than the ring structure (energy is 6.04 kJ / mol), the energy barriers of conversion are 13.15 kJ / mol (linear → cyclic) and 7.11 kJ / mol ( Ring → linear). Thermodynamic and kinetic calculations show that NaN3 usually exists as a linear structure (accounting for more than 85%) and increases with increasing temperature (greater than 91% at 1000K).