Advanced ab initio and hybrid density functional theory evaluation of the atomization energies, bond dissociation pathways, and heats of formation of the two isomers of HClO4

摘要: Abstract The reliability of various ab initio and density functional theory models has been evaluated in the past for study bond dissociation energies, heats formation, etc [1] , [2] [3] . We present two novel results, first being evidence formation HO4Cl, isomer, as well effect basis set choice a molecular orbital calculation these types systems. For all methods we have employed B3LYP method with 6-311++G (d, p), (2d, 2p), (3d, 3p), (3df, 3pd) sets found that predicted energies yield higher energy second isomer HClO4, HOClO3, but when very large was used (6-311++G 3pd)) latter to be lower than former, which is correlation previously published results same unusual were seen Hartree–Fock (HF), MP2, MP4 where 6-31G(d), 6-31G(d′), 6-311G(d, p) unable correlate (to reasonable extent MP2 methods) experimental value around 4 kcal/mol heat HOClO3 unless CBSB3 or CBSB4 implemented. also investigated five possible channels radical mechanisms atomization isomers at methods, sets.