双电子体系(H_2O)_(12)^(2-)的结构及额外电子定位研究

THEORETICAL RESEARCH ON THE STRUCTURES AND EXCESS ELECTRON LOCALIZATION OF THE DIELECTRON (H_2O)_(12)^(2-)

采用密度泛函结合对称性破损(DFT-UBS)方法研究了水分子团簇(H_2O)_(12)^(2-)双电子体系的结构、稳定性及电场诱导下的额外电子定位。计算显示(H_2O)_(12)^(2-)的两种结构(1和2)都以单态为稳定态,其中2是独特的开壳型单态双自由基,其两个自由基电子(HOMO(α)和(β))分居于分子的两端。在外电场(0.0033≤Fz≤0.0256 au)的诱导下,一端的自由基电子可以迁移到另一电子一端而不明显改变体系的单态双自由基特征。

Using unrestricted broken spin-symmetry density functional theory （UBS-DFT）, the dielectron （H2O）122- cluster’s structures, stabilities, and the excess electron localizations under the inducement of external electric field were investigated. Our calculations indicate that the stable ground states are singlet states for both of the two structures （1 and 2）. Especially, 2 exhibits open-shell singlet diradical characteristics. The two singlet radical electrons （HOMO（α） and （β）） of 2 are, respectively, mainly localized in the different ends of the structure. Under the inducement of external electric field （0.0033≤Fz≤0.0257 au）, one radical electron transfers from one end to the another end （due to the repulsion of the other radical electron） without obvious change of singlet diradical characteristic.