Quantum chemical and molecular dynamics study on the hydration of cyanide and thiocyanate anions

✍ Scribed by Roland Sansone; Christoph Ebner; Michael Probst

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 728 KB
• Volume: 88
• Category: Article
• ISSN: 0167-7322
• DOI: 10.1016/s0167-7322(00)00149-5

✦ Synopsis

The interaction of the anions CN-and SCN-with water has been investigated with by methods of computational chemistry. Complexes of CN-and SCNwith water show near-linear hydrogen bonds with binding energies of about -67 (CN-) and -54 (SCN-) kJ/mol. Coordination to the N-site is preferred over the C or S site. Intermolecular potential functions and intramolecular force fields of were derived from ab-initio calculated energies. We have performed molecular dynamics simulations in the NVT ensemble on solvated cyanide and thiocyanate anions. The simulated systems consisted of one anion each, about 300 water molecules and potassium ion as the countercation. The simulations show a pronounced first and a partially ordered second hydration she11. The similarities of the potential surface between CN-and SCN-extent to most properties calculated by the MD simulation but for hydrated CN-linear X...O-H hydrogen bonds dominate, whereas in SCNdipolar configurations seem to be more prominent.