The visible region of the electronic absorption spectra of Cu(II) complexes was studied by time-dependent density functional theory (TD-DFT). The performance of twelve functionals in the prediction of absorption maxima (λmax) was tested on eleven compounds with different geometry, donors and charge. The ranking of the functionals for λmax was determined in terms of mean absolute percent deviation (MAPD) and standard deviation (SD) and it is as follows: BHandHLYP > M06 ≫ CAM-B3LYP ≫ MPW1PW91 ~ B1LYP ~ BLYP > HSE06 ~ B3LYP > B3P86 ~ ω-B97x-D ≫ TPSSh ≫ M06-2X (MAPD) and BHandHLYP > M06 ~ HSE06 > ω-B97x-D ~ CAM-B3LYP ~ MPW1PW91 > B1LYP ~ B3LYP > B3P86 > BLYP ≫ TPSSh ≫ M06-2X (SD). With BHandHLYP functional the MAPD is 3.1% and SD is 2.3%, while with M06 the MAPD is 3.7% and SD is 3.7%. The protocol validated in the first step of the study was applied to: i) calculate the number of transitions in the spectra and relate them to the geometry of Cu(II) species; ii) determine the coordination of axial water(s); iii) predict the electronic spectra of the systems where Cu(II) is bound to human serum albumin (HSA) and to the regions 94-97 and 108-112 of prion protein (PrP). The results indicate that the proposed computational protocol allows a successful prediction of the electronic spectra of Cu(II) species and to relate an experimental spectrum to a specific structure.

中文翻译：

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铜（II）-生物配体系统电子吸收光谱的定量预测：验证和应用。

利用时变密度泛函理论（TD-DFT）研究了Cu（II）配合物的电子吸收光谱的可见区。在11种具有不同几何形状，给体和电荷的化合物上测试了十二种功能预测最大吸收（λmax）的性能。根据平均绝对百分比偏差（MAPD）和标准偏差（SD）确定λmax的功能等级，如下所示：BHandHLYP> M06≫ CAM-B3LYP≫ MPW1PW91〜B1LYP〜BLYP> HSE06〜B3LYP> B3P86 〜ω-B97x-D≫ TPSSh≫ M06-2X（MAPD）和BHandHLYP> M06〜HSE06>ω-B97x-DCAM-B3LYP〜MPW1PW91> B1LYP〜B3LYP> B3P86> BLYP≫ TPSSh≫ M06-2X（SD） 。具有BHandHLYP功能的MAPD为3.1％，SD为2.3％，而具有M06的MAPD为3.7％，SD为3.7％。在研究的第一步中验证的协议可用于：i）计算光谱中的跃迁数，并将其与Cu（II）物种的几何形状相关；ii）确定轴向水的配比；iii）预测其中Cu（II）与人血清白蛋白（HSA）以及病毒蛋白（PrP）的94-97和108-112区结合的系统的电子光谱。结果表明，提出的计算协议可以成功预测Cu（II）物种的电子光谱，并将实验光谱与特定结构相关联。iii）预测其中Cu（II）与人血清白蛋白（HSA）以及病毒蛋白（PrP）的94-97和108-112区结合的系统的电子光谱。结果表明，提出的计算协议可以成功预测Cu（II）物种的电子光谱，并将实验光谱与特定结构相关联。iii）预测其中Cu（II）与人血清白蛋白（HSA）以及病毒蛋白（PrP）的94-97和108-112区结合的系统的电子光谱。结果表明，提出的计算协议可以成功预测Cu（II）物种的电子光谱，并将实验光谱与特定结构相关联。