A theoretical study of malonate ion and its metal binding by ab initio and semiempirical techniques

STO-3G and CNDO calculations have been performed on malonate ion and its Mg²⁺ complexes. The parallel carboxyl group arrangement is found to be the single minimum energy conformation with both techniques. In the metal binding studies, the binding of a Mg²⁺ to a single carboxyl is preferred over binding symmetrically to both carboxyls in their parallel conformation. These results are consistent with X-ray structure results on calcium malonate.