Using the density functional method B3LYP/6-311G(d,p) calculations, the inhibitor activity of 4-allyl-5-(pyridin-4-yl)-4H-1,2,4-triazole-3-thiol tautomerism against corrosion of neutral copper surfaces has been investigated. Among the inhibitors tested, the 4-allyl-5-(pyridin-4-yl)-4H-1,2,4-triazole-3-thiol inhibitor has the inhibition performance for both forms (thiol and thione). Quantum chemical parameters that are correlated to the inhibition efficiency including highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital, (LUMO), energy bandgap (ΔE), electronegativity (χ), Hardness (ɳ), softness (σ), dipole moment (μ), the fraction of the electrons transferred (ΔE), and Total energy (TE) has been calculated. In addition, the adsorption of inhibitors on the neutral copper surface reveals that nitrogen adsorption is preferred over sulfur adsorption. The results show that the thione form has the highest inhibitor compared to the thiol form.

中文翻译：

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4-allyl-5-(pyridin-4-yl)-4H-1,2,4-triazole-3-thiol-thione互变异构体缓蚀剂活性的理论测定

使用密度泛函法 B3LYP/6-311G(d,p) 计算，4-allyl-5-(pyridin-4-yl)-4H-1,2,4-triazole-3-thiol 互变异构的抑制剂活性已经研究了中性铜表面的腐蚀。在所测试的抑制剂中，4-allyl-5-(pyridin-4-yl)-4H-1,2,4-triazole-3-thiol 抑制剂对两种形式（硫醇和硫酮）都有抑制性能。与抑制效率相关的量子化学参数包括最高占据分子轨道 (HOMO)、最低未占据分子轨道 (LUMO)、能带隙 (ΔE)、电负性 (χ)、硬度 (ɳ)、柔软度 (σ)、偶极子矩 (μ)、电子转移的分数 (ΔE) 和总能量 (TE) 已被计算出来。此外，抑制剂在中性铜表面的吸附表明氮吸附优于硫吸附。结果表明，与硫醇形式相比，硫酮形式具有最高的抑制剂。