Yin Xiaoke, Li Xiaojun
School of Fine Arts, Weinan Normal University, Weinan, China.
School of Chemical Engineering, Xi'an University, Xi'an, China.
J Mol Model. 2021 Mar 15;27(4):108. doi: 10.1007/s00894-021-04718-z.
The molecular structures, electronic properties, and the UV-vis absorption spectra of the oxides of mineral green pigment (MGP) have been theoretically calculated by using the density-functional theory (DFT) method. Our results reveal that the ground-state structure (isomer-I) of the oxides takes on an O-bridged bond with the polycyclic ring. The chemical stabilities of the oxides (I-V) are gradually reduced, of which the I isomer has the largest gap (2.50 eV). Moreover, the adsorption of the two oxygen atoms tailors the electronic structures of oxides, and the electronic properties are keys to understand the structural stabilization of the complexes. Additionally, the strongest UV-vis absorption band of the I isomer has been assigned; e.g., the crucial excitation originates from a HOMO-17→LUMO (32%) transition at ~ 187.3 nm.
采用密度泛函理论（DFT）方法对矿物绿色颜料（MGP）氧化物的分子结构、电子性质和紫外可见吸收光谱进行了理论计算。我们的结果表明，氧化物的基态结构（异构体-I）与多环形成O-桥键。氧化物（I-V）的化学稳定性逐渐降低，其中I异构体的能隙最大（2.50 eV）。此外，两个氧原子的吸附调整了氧化物的电子结构，电子性质是理解配合物结构稳定性的关键。此外，还确定了I异构体最强的紫外可见吸收带；例如，关键激发源于~187.3 nm处的HOMO-17→LUMO（32%）跃迁。
