Bode Arno A C, Granneman Sanne J C, Feiters Martin C, Verwer Paul, Jiang Shanfeng, Meijer Jan A M, van Enckevort Willem J P, Vlieg Elias
Radboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands.
AkzoNobel Industrial Chemicals, Salts and Crystallization, Deventer, The Netherlands.
Dalton Trans. 2016 Apr 21;45(15):6650-9. doi: 10.1039/c6dt00098c.
Iron(III) meso-tartrate, a metal-organic complex, is a new anticaking agent for sodium chloride. A molecular structure in solution is proposed, based on a combination of experimental and molecular modelling results. We show that the active complex is a binuclear iron(iii) complex with two bridging meso-tartrate ligands. The iron atoms are antiferromagnetically coupled, resulting in a reduced paramagnetic nature of the solution. In solution, a water molecule coordinates to each iron atom as a sixth ligand, resulting in an octahedral symmetry around each iron atom. When the water molecule is removed, a flat and charged site is exposed, matching the charge distribution of the {100} sodium chloride crystal surface. This charge distribution is also found in the iron(iii) citrate complex, another anticaking agent. This gives a possible adsorption geometry on the crystal surface, which in turn explains the anticaking activity of the iron(III) meso-tartrate complex.
酒石酸铁（III）是一种金属有机配合物，是一种新型的氯化钠抗结剂。基于实验和分子模拟结果，提出了其在溶液中的分子结构。我们表明，活性配合物是一种具有两个桥连酒石酸配体的双核铁（III）配合物。铁原子通过反铁磁耦合，导致溶液的顺磁性降低。在溶液中，一个水分子作为第六个配体与每个铁原子配位，导致每个铁原子周围具有八面体对称性。当水分子被去除时，一个平坦且带电的位点暴露出来，与{100}氯化钠晶体表面的电荷分布相匹配。这种电荷分布在另一种抗结剂柠檬酸铁（III）配合物中也有发现。这给出了在晶体表面可能的吸附几何结构，进而解释了酒石酸铁（III）配合物的抗结活性。
