Solution structure determination of tetranuclear platinum(II) cluster complex in acetic acid: X-ray diffraction and molecular dynamics simulation study

X-ray diffraction and molecular dynamics simulation studies were performed in order to describe the structure of [Pt(CH3COO)(2)](4) complex in acetic acid. Structural information about the solution, the solvated complex, further on the often-neglected complex-solvent interactions in solution are discussed. Finally the change in the bulk structure of the solvent due to the presence of a complex solvate was also studied. The good agreement between the diffraction experiments and the results of molecular dynamics simulations justify the use of simulations in order to obtain a detailed description of the liquid structure by using partial radial distribution functions and hydrogen bond statistics. Acetic acid is described as a strong hydrogen bonding liquid, where the molecules mainly form a chain structure by hydrogen bonds but cyclic structures can also be identified. The bulk structure of the solution is only slightly affected by the solvation of the complex. On the basis of bonding and nonbonding Pt...Pt interactions obtained from X-ray diffraction results it can be stated that the [Pt(CH3COO)(2)](4) complex maintains its shape in solution. An analysis of complex-solvent intermolecular interaction showed that only a very weak and diffuse solvation sphere is formed around the solvated complex. (C) 2008 Elsevier B.V. All rights reserved.