Structure and dynamics of the CrIII ion in aqueous solution: Ab initio QM/MM molecular dynamics simulation |
| |
Authors: | Kritayakornupong Chinapong Plankensteiner Kristof Rode Bernd M |
| |
Institution: | Department of Theoretical Chemistry, Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, A-6020 Innsbruck, Austria. |
| |
Abstract: | Structural and dynamical properties of the Cr(III) ion in aqueous solution have been investigated using a combined ab initio quantum mechanical/molecular mechanical (QM/MM) molecular dynamics simulation. The hydration structure of Cr(III) was determined in terms of radial distribution functions, coordination numbers, and angular distributions. The QM/MM simulation gives coordination numbers of 6 and 15.4 for the first and second hydration shell, respectively. The first hydration shell is kinetically very inert but by no means rigid and variations of the first hydration shell geometry lead to distinct splitting in the vibrational spectra of Cr(H(2)O)(6) (3+). A mean residence time of 22 ps was obtained for water ligands residing in the second hydration shell, which is remarkably shorter than the experimentally estimated value. The hydration energy of -1108 +/- 7 kcal/mol, obtained from the QM/MM simulation, corresponds well to the experimental hydration enthalpy value. |
| |
Keywords: | ion hydration Cr(III) ligand exchange librational/vibrational spectra |
本文献已被 PubMed 等数据库收录! |
|