Abstract
The optical absorption of small water clusters, water chains, liquid water, and crystalline ice is analyzed computationally. We identify two competing mechanisms determining the onset of the optical absorption: Electronic transitions involving surface molecules of finite clusters or chains cause a redshift upon molecular aggregation compared to monomers. On the other hand, a strong blueshift is caused by the electrostatic environment experienced by water monomers embedded in a hydrate shell. Concerning the recent dispute over the structure of the liquid, the present results support the conventional fourfold coordinated water, as obtained from ab initio molecular-dynamics simulations.
- Received 7 January 2008
DOI:https://doi.org/10.1103/PhysRevLett.100.207403
©2008 American Physical Society