[复习]NBO输出结果分析.doc

NBO输出结果分析 NBO 结果输出内容（1）2008-10-24 13:091.NATURAL POPULATIONS: Natural atomic orbital occupancies For each of the 28 NAO functions, this table lists the atom to which the NAO is attached, the angular momentum type (s, px, etc.), the orbital type (whether core, valence, or Rydberg, with a conventional hydrogenic-type label), the orbital occupancy (number of electrons, or natural population of the orbital), and the orbital energy (in atomic units: 1 a.u. = 627.5 kcal/mol). Note that the occupancies of the Rydberg (Ryd) NAOs are typically much lower than those of the core (Cor) and valence (Val) NAOs of the natural minimum basis (NMB) set, reflecting the dominant role of the NMB orbitals in describing molecular properties. 2. Summary of Natural Population Analysis: This segment is an atomic summary showing the natural atomic charges (nuclear charge minus summed natural populations of NAOs on the atom) and total core, valence, and Rydberg populations on each atom: 3. Natural Population analesis Core 3.99900 ( 99.9749% of 4) Valence 13.97712 ( 99.8366% of 14) Natural Minimal Basis 17.97612 ( 99.8673% of 18) Natural Rydberg Basis 0.02388 ( 0.1327% of 18) This reveals the high percentage contribution (typically, 99%) of the NMB set to the molecular charge distribution. 4. Finally, the natural populations are summarized as an effective valence electron configuration (natural electron configuration) for each atom: Atom No Natural Electron Configuration C 1 [core] 2S( 1.08) 2p( 3.40) N 2 [core] 2S( 1.43) 2p( 4.47)3p( 0.01) H 3 1S( 0.77) H 4 1S( 0.80) H 5 1S( 0.77) H 6 1S( 0.62) H 7 1S( 0.62) Although the occupancies of the atomic orbitals are non-integer in the molecular environment, the effective atomic configurations can be related to idealized atomic s