Covalent dimers of CL-20 (a), CSi5H6N12O12 (b) – (d) and C4Si2H6N12F12 (e) – (l). The lowest energy dimers of CL-20, CSi5H6N12O12, and C4Si2H6N12F12 are labeled as D1-(1), D2-(1), and D3-(1), respectively. Energy differences between every dimer and the corresponding low-energy dimer are presented in eV. Optimized coordinates of these compounds are also available in Supplementary Materials.