The complexation of magnesium with hydrogen malonate and formate anions was studied with ab initio calculations. At least HF/6-31G∗ level of accuracy is necessary for a qualitatively correct description of the complexes. The coordination space of magnesium has to be filled to attain reliable results. If crystal structures are used as experimental references, at least part of the crystal interactions must be properly included in the calculations.
Yliniemelä, A., Uchimaru, T., Hirose, T., Baldwin, B., & Tanabe, K. (1996). A computational study on magnesium complexation with formate and hydrogen malonate anions. Journal of Molecular Structure, 369(1-3), 9-22. https://doi.org/10.1016/S0166-1280(96)04641-6