A Theoretical Investigation of the Ring Strain Energy, Destabilization Energy, and Heat of Formation of CL-20
Figure 2
(a) Effect of –NH– and –NO2 substitution on the strainless gas-phase heat of formation of isowurtzitane. Closed squares: effect on the strainless heat of formation of adding –NH– groups to isowurtzitane in the 2, 4, 6, 8, 10 and 12 positions, open squares: effect on the strainless heat of formation of adding –NO2 groups to isowurtzitane in the 2, 4, 6, 8, 10 and 12 positions, open circles: effect on the strainless heat of formation of adding –NH– groups to 2,4,6,8,10,12-hexanitroisowurtzitane in the 2, 4, 6, 8, 10 and 12 positions, closed triangles: Effect on the strainless heat of formation of adding –NO2 groups to 2,4,6,8,10,12-hexaazaisowurtzitane in the 2, 4, 6, 8, 10 and 12 positions, tilted open squares: effect on the strainless heat of formation of adding >N–NO2 groups to isowurtzitane in the 2, 4, 6, 8, 10 and 12 positions. (b) Effect of –NH– and –NO2 substitution on the gas phase heat of formation of isowurtzitane calculated using the T1 multilevel ab initio model chemistry approach described by Ohlinger et al. [15]. Closed squares: effect on the heat of formation of adding –NH– groups to isowurtzitane in the 2, 4, 6, 8, 10 and 12 positions, Open squares: Effect on the heat of formation of adding –NO2 groups to isowurtzitane in the 2, 4, 6, 8, 10 and 12 positions, Open circles: Effect on the heat of formation of adding –NH– groups to 2,4,6,8,10,12-hexanitroisowurtzitane in the 2, 4, 6, 8, 10 and 12 positions, Closed triangles: effect on the heat of formation of adding –NO2 groups to 2,4,6,8,10,12-hexaazaisowurtzitane in the 2, 4, 6, 8, 10 and 12 positions, tilted open squares: effect on the heat of formation of adding >N–NO2 groups to isowurtzitane in the 2, 4, 6, 8, 10 and 12 positions.
