The first structural examples of tricitratotitanate [Ti(H2cit)3]2- dianions

The crystal structures of the mixed-cation compounds Mg-1/2[Ti(H(2)cit)(3)].6H(2)O and (NH4)Mg-1/2[Ti(H(2)cit)(3)].-6H(2)O (H(4)cit = citric acid), which were synthesized by a modified Pechini process, feature three bidentate [(HO2CCH2)(2)C(CO2-)O-] citrato groups that chelate to the titanium atom through their negatively-charged alpha-alkoxyl and alpha-carboxyl oxygen atoms; the other two beta-carboxylic acid groups are free.