Temperature dependence of structure and dynamics of the hydrated Ca2+ ion according to ab initio quantum mechanical charge field and classical molecular dynamics

✍ Scribed by Len Herald V. Lim; Andreas B. Pribil; Andreas E. Ellmerer; Bernhard R. Randolf; Bernd M. Rode

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 252 KB
• Volume: 31
• Category: Article
• ISSN: 0192-8651
• DOI: 10.1002/jcc.21405

✦ Synopsis

Abstract

Simulations using ab initio quantum mechanical charge field molecular dynamics (QMCF MD) and classical molecular dynamics using two‐body and three‐body potentials were performed to investigate the hydration of the Ca^2+^ ion at different temperatures. Results from the simulations demonstrate significant effects of temperature on solution dynamics and the corresponding composition and structure of hydrated Ca^2+^. Substantial increase in ligand exchange events was observed in going from 273.15 K to 368.15 K, resulting in a redistribution of coordination numbers to lower values. The effect of temperature is also visible in a red‐shift of the ion‐oxygen stretching frequencies, reflecting weakened ligand binding. Even the moderate increase from ambient to body temperature leads to significant changes in the properties of Ca^2+^ in aqueous environment. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010