The excited states of mustard and related alkyl sulfides have been calculated using time-dependent density functional theory. Among the seven commonly used density functionals, PBE0 exhibits the most accurate excited energy, while the Pearson-related coefficient of calculated energies and experimental peaks reaches 0.98. Boltzmann average analysis reveals that excited energies of different conformers are almost the same. The calculated excited states of mustard come to 5.56 and 6.00 eV, which are assigned as n → σ* transition by the natural transition orbital visualization. Besides, sulfur ethers with C_2ν symmetry show similar ultraviolet properties as mustard, whereas the excited states of simulated agents with the SCH₂CH₂Cl group differ from mustard.

中文翻译：

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时变密度泛函理论计算某些烷基硫化物的激发态

芥子油和相关烷基硫化物的激发态已使用时变密度泛函理论进行了计算。在七个常用的密度泛函中，PBE0表现出最准确的激发能，而与皮尔逊相关的计算出的能量和实验峰值系数达到0.98。玻尔兹曼平均分析表明，不同构象异构体的激发能几乎相同。计算得出的芥子激发态分别为5.56和6.00 eV，通过自然跃迁轨道可视化将其分配为n→σ*跃迁。此外，具有_C2ν对称性的_硫醚显示出与芥末相似的紫外线性质，而具有SCH ₂ CH ₂ Cl基团的模拟试剂的激发态与芥末有所不同。