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选用B3LYP方法在LanL2MB水平下,对双帽α-Keggin型杂多阴离子[H4As3Mo12O40]–的电子结构和质子的定位进行了密度泛函理论(DFT)研究.结果表明,双帽的形成大大影响了杂多阴离子[As3Mo12O40]5-的电子结构和性质,NBO分析显示参与成帽的三桥氧上的电子密度比双桥氧上的要大,简单地从电荷密度来看,质子将首先在三桥氧上定域成键,但通过比较质子定域在几种桥氧上质子化稳定化能的大小,发现[H4As3Mo12O40]–中的四个质子将在八个双桥氧中的其中四个氧原子上定位,而不是如文献中报道的在四个三桥氧上定域成键.对杂多酸H3PM12O40(M=Mo,W)中质子的定位也进行了理论计算并与文献进行了比较,结果显示,H3PMo12O40中质子是定位在双桥氧上;而H3PW12O40中质子将优先在双桥氧上定位,但也可在端氧上定位;这一结果与文献报道的相一致.
Density functional theory (DFT) studies of the electronic structure and proton localization of the double-cap α-Keggin-type heteropolyanion [H4As3Mo12O40] were performed using the B3LYP method at the LanL2 MB level. The results showed that the formation of the double cap greatly affected The electronic structure and properties of heteropolyanion [As3Mo12O40] 5, NBO analysis show that the electron density of the triple bridge oxygen involved in cap formation is larger than that of double bridged oxygen. Simply from the charge density perspective, Bridged oxygen delocalized into bonds, but by comparing proton localized protonation stabilization energies across several bridging oxygen, it was found that four of the protons in [H4As3Mo12O40] Rather than the site-bound bonds on the four tris-bridge oxygen as reported in the literature.The localization of protons in the heteropolyacid H3PM12O40 (M = Mo, W) has also been theoretically calculated and documented The results show that the proton in H3PMo12O40 is located on the double bridge oxygen while the proton in H3PW12O40 will preferentially locate on the double bridge oxygen but also on the terminal oxygen. This result is consistent with that reported in the literature.