title: Structure and activity of the anticaking agent iron(III) meso-tartrate.
abstract: 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.
authors.affiliation: Radboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands. W.vanEnckevort@science.ru.nl.
authors.forename: Arno A C
authors.initials: AA
authors.lastname: Bode
authors.affiliation: Radboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands. W.vanEnckevort@science.ru.nl.
authors.forename: Sanne J C
authors.initials: SJ
authors.lastname: Granneman
authors.affiliation: Radboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands. W.vanEnckevort@science.ru.nl.
authors.forename: Martin C
authors.initials: MC
authors.lastname: Feiters
authors.affiliation: AkzoNobel Industrial Chemicals, Salts and Crystallization, Deventer, The Netherlands.
authors.forename: Paul
authors.initials: P
authors.lastname: Verwer
authors.affiliation: AkzoNobel Industrial Chemicals, Salts and Crystallization, Deventer, The Netherlands.
authors.forename: Shanfeng
authors.initials: S
authors.lastname: Jiang
authors.affiliation: AkzoNobel Industrial Chemicals, Salts and Crystallization, Deventer, The Netherlands.
authors.forename: Jan A M
authors.initials: JA
authors.lastname: Meijer
authors.affiliation: Radboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands. W.vanEnckevort@science.ru.nl.
authors.forename: Willem J P
authors.initials: WJ
authors.lastname: van Enckevort
authors.affiliation: Radboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands. W.vanEnckevort@science.ru.nl.
authors.forename: Elias
authors.initials: E
authors.lastname: Vlieg