A Giant Polyaluminum Species S-Al-32 and Two Aluminum Polyoxocations Involving Coordination by Sulfate Ions S-Al-32 and S-K-Al-13

作者：Sun, Zhong^*; Wang, Hui; Tong, Honggeer; Sun, Shaofan

来源：Inorganic Chemistry, 2011, 50(2): 559-564.

DOI：10.1021/ic101875r

• CRYSTAL-STRUCTURE
• AQUEOUS-SOLUTION
• OXYGEN-EXCHANGE
• SALTS
• HYDROLYSIS
• SPECIATION
• COMPLEXES
• CLUSTER
• MODEL
• AL-30

The giant polyaluminum species [Al32O8(OH)(60)(H2O)(28)(SO4)(2)](16+) (S-Al and [Al13O4(OH)(25)(H2O)(10)(SO4)](4+) (S-K-Al-13) [S means that sulfate ions take part in coordination of the aluminum polycation; K represents the Keggin structure] were obtained in the structures of [Al32O8(OH)(60)(H2O)(28)(SO4)(2)][SO4](7)[Cl](2)center dot 30H(2)O and [Al13O4(OH)(25)(H2O)(10)(SO4)](3)center dot 20H(2)O, respectively. They are the first two aluminum polyoxocations coordinated by sulfate ions. The "corn-shell" structure of S-Al-32 is similar to that of Al-30, but the units are linked by two [Al(OH)(2)(H2O)(3)(SO4)] groups with replacement of four eta(1)-H2O molecules. The structure of S-K-Al-13 is similar to the well-known structure of epsilon-K-Al-13, but the units are linked by two (SO42-)(0.5) with replacement of a H3O+ ion. It was shown that strong interact on exists between the polyoxocations and counterions. On the basis of their structural features and preparation conditions, a formation and evolution mechanism (from epsilon-K-Al-13 to S-K-Al-13 and S-Al-32) has been proposed. A local basification degree symmetrical equalization principle was extracted based on a comparison of the calculated results of the local basification degree for each central Al3+ ion included in a polycation. They can be used to explain how the two aluminum species are formed and evolved and why the sulfate ions can coordinate to them and to predict where he OH-bridging positions will be upon further hydrolysis.

• 出版日期2011-1-17
• 单位内蒙古大学