Kinrade Stephen D., Knight Christopher T. G., Pole David L., Syvitski Raymond T.
Department of Chemistry, Lakehead University, Thunder Bay, Ontario, P7B 5E1, Canada, and School of Chemical Sciences, University of Illinois at Urbana-Champaign, 505 South Mathews Avenue, Urbana, Illinois 61801.
Inorg Chem. 1998 Aug 24;37(17):4272-4277. doi: 10.1021/ic971629e.
The addition of tetraalkylammonium cations to aqueous silicate solutions enhances the abundance of symmetric, cagelike, polysilicate anions including the cubic octamer, Si(8)O(20)(8)(-). The equilibrium ratio of tetramethylammonium (TMA) cations to the octameric silicate anion is 8:1 for solutions with a concentration ratio [OH(-)]:[Si] >/= 1:1. Evidence indicates that organocations directly associate with cagelike polyanions to form a protective shell of hydrophobic hydration that impedes hydrolysis of the central anion.
向硅酸盐水溶液中添加四烷基铵阳离子可提高对称的、笼状多硅酸盐阴离子的丰度，其中包括立方八聚体Si(8)O(20)(8)(-)。对于[OH(-)]:[Si]≥1:1的溶液，四甲基铵（TMA）阳离子与八聚硅酸盐阴离子的平衡比为8:1。有证据表明，有机阳离子直接与笼状聚阴离子缔合，形成一个疏水水合的保护壳，从而阻碍中心阴离子的水解。
