Estimated Adiabatic Ionization Energies for Organic Compounds Using the Gaussian-4 (G4) and W1BD Theoretical Methods

Gas phase (298.15 K, 101.325 kPa) adiabatic ionization energies (AIEs) were calculated for 236 organic compounds with the Gaussian-4 (G4) composite method and for 17 molecules at the W1BD level of theory. Functional group types considered span a range of mono- and polyfunctionalized halogenated, saturated and unsaturated, cyclic and acyclic, and heteroatom (N, O, S) substituted moieties without substantial conformational complexity. Excellent agreement was found using both computational methods against available experimental data. Approximately equivalent AIE prediction accuracy was observed between the G4 and the W1BD methods. For compounds with well-constrained experimental AIEs, both levels of theory provide effective chemical accuracy.

本研究针对236种有机化合物，采用Gaussian-4（G4）复合方法计算了其在298.15 K、101.325 kPa气相条件下的绝热电离能（adiabatic ionization energies, AIEs），并针对17个分子采用W1BD理论水平完成了同类计算。所覆盖的官能团类型包含单官能化与多官能化的卤代、饱和与不饱和、环状与非环状，以及杂原子（N、O、S）取代的基团，且无显著构象复杂性。两种计算方法均与现有实验数据呈现极佳的一致性；G4与W1BD方法的AIE预测精度大致相当。对于实验绝热电离能约束良好的化合物，两种理论水平均可实现有效的化学精度。