Theoretical study of metastable N2CO isomers. New candidates for high energy materials?

✍ Scribed by Anatoli A. Korkin; Paul von Ragué Schleyer; Russell J. Boyd

• Book ID: 103031104
• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 594 KB
• Volume: 227
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(94)00822-1

✦ Synopsis

The geometries, energies and frequencies of singlet and triplet N&O isomers were computed ab initio at the HF/6-31G*, MP2/6-3 1 +G* and at the BECKE3LYP/6-3 1 1 + G* levels. Single point energies were calculated at the QCISD( T) /6-3 1 1 + G*//MP2/6-31 +G* level and at the CCSD(T)/6-311 +G(2D)//BECKE3LYP/6-311 +G* level. The most stable bound N&O isomer is the unknown three-membered cyclic CsV structure (diazirinone); its aromatic stabilization energy is only 7 kcal/mol. Dissociation of diazirinone into N2 and CO is exothermic by 96-100 kcal/mol, but the 27 kcal/mol barrier is sufficiently high to permit observation. The open-chain NNCO triplet lies 5 kcal/mol above diazirinone and z 35 kcal/mol below the spinallowed dissociation into X 'Z: N2 and 'II, CO. While the known nitrosyl cyanide (NCNO) is 11 kcal/mol less stable than diazirinone, the dissociation into CN and NO radicals is endothermic by 47-50 kcal/mol.