Helmholtz-Zentrum Dresden-Rossendorf, Institute of Resource Ecology, Bautzner Landstr. 400, D-01314 Dresden, Germany.
Dalton Trans. 2012 Nov 7;41(41):12818-23. doi: 10.1039/c2dt31367g. Epub 2012 Sep 14.
A hexanuclear Th(IV)-glycine complex was observed by Th L(3)-edge EXAFS measurements in an aqueous solution. Within the stability range of this complex the positively charged hexanuclear species Th(6)(μ(3)-O)(4)(μ(3)-OH)(4)(H(2)O)(6)(Gly)(6)(HGly)(6) was preserved in a crystal with the composition [Th(6)(μ(3)-O)(4)(μ(3)-OH)(4)(H(2)O)(6)(Gly)(6)(HGly)(6)]·(NO(3))(3)(ClO(4))(3)(H(2)O)(3). This complex appears as a result of a competing reaction between hydrolysis and ligation by glycine. At a pH value below the stability range of the hexanuclear complex, crystals with the composition [Th(H(2)O)(3)(HGly)(3)]·(ClO(4))(4)H(2)O were obtained from the solution. Three water molecules in the thorium coordination sphere indicate that this complex occurs prior to the onset of Th(IV) hydrolysis.
在水溶液中，通过 Th L(3)-边 EXAFS 测量观察到了一个六核 Th(IV)-甘氨酸配合物。在该配合物的稳定范围内，带正电荷的六核物种 Th(6)(μ(3)-O)(4)(μ(3)-OH)(4)(H(2)O)(6)(Gly)(6)(HGly)(6) 在组成为 [Th(6)(μ(3)-O)(4)(μ(3)-OH)(4)(H(2)O)(6)(Gly)(6)(HGly)(6)]·(NO(3))(3)(ClO(4))(3)(H(2)O)(3)的晶体中得以保留。该配合物是水解和甘氨酸配位之间竞争反应的结果。在六核配合物稳定范围的 pH 值以下，从溶液中获得了组成式为 [Th(H(2)O)(3)(HGly)(3)]·(ClO(4))(4)H(2)O 的晶体。在钍配位体中三个水分子表明，在 Th(IV)水解开始之前，就已经存在这种配合物。
