Beardmore James, Lopez Xabier, Mujika Jon I, Exley Christopher
Birchall Centre, Lennard-Jones Laboratories, Keele University, Staffordshire, ST5 5BG, UK.
Kimika Fakultatea, Euskal Herriko Unibertsitatea UPV/EHU, and Donostia International Physics Center (DIPC), P.K. 1072, 20080 Donostia, Euskadi, Spain.
Sci Rep. 2016 Aug 1;6:30913. doi: 10.1038/srep30913.
The formation of hydroxyaluminosilicates is integral to the biogeochemical cycles of aluminium and silicon. The unique inorganic chemistry which underlies their formation explains the non-essentiality in biota of both of these elements. However, the first steps in the formation of hydroxyaluminosilicates were hitherto only theoretical and plausibly only accessible in silico. Herein we have used computational chemistry to identify and define for the first time these unique and ultimately critically important reaction steps. We have used density-functional theory combined with solvent continuum models to confirm first, the nature of the reactants, an aluminium hydroxide dimer and silicic acid, second, the reaction products, two distinct hydroxyaluminosilicates A and B and finally, how these are the precursors to highly insoluble hydroxyaluminosilicates the role of which has been and continues to be to keep inimical aluminium out of biota.
羟基铝硅酸盐的形成是铝和硅生物地球化学循环不可或缺的一部分。其形成所基于的独特无机化学解释了这两种元素在生物群中并非必需的原因。然而，迄今为止，羟基铝硅酸盐形成的最初步骤仅存在于理论层面，并且可能仅在计算机模拟中得以实现。在此，我们运用计算化学首次识别并定义了这些独特且最终至关重要的反应步骤。我们使用密度泛函理论结合溶剂连续介质模型，首先确认了反应物——氢氧化铝二聚体和硅酸的性质，其次确认了反应产物——两种不同的羟基铝硅酸盐A和B，最后确认了它们如何作为高度不溶性羟基铝硅酸盐的前体，其作用一直以来并且仍在持续，即防止有害铝进入生物群。
