BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Stabilization of AgI’s polar surfaces by the aqueous environment
 \, and its implications for ice formation - Dr Stephen Cox\, University of
  Cambridge
DTSTART:20190501T131500Z
DTEND:20190501T141500Z
UID:TALK115654@talks.cam.ac.uk
CONTACT:Lisa Masters
DESCRIPTION:Silver iodide is probably the best inorganic ice nucleating pa
 rticle known\, a feature generally attributed to the excellent lattice mat
 ch between its basal crystal faces and ice. However\, the polar nature of 
 this crystal termination means the surface energy diverges with crystal si
 ze unless a polarity compensation mechanism prevails. In this simulation s
 tudy\, the extent to which the surrounding aqueous environment is able to 
 provide such polarity compensation is investigated. On its own\, it is fou
 nd that pure water is unable to stabilize the AgI crystal in a physically 
 reasonable manner\, and that mobile charge carriers such as dissolved ions
 \, are essential. In other words\, proximate dissolved ions must be consid
 ered an integral part of the heterogeneous ice formation mechanism.\n\nThi
 s work relies on recent advances in simulation methodology in which approp
 riate electric and electric displacement fields are imposed ("finite field
  methods"). A useful by-product of this study is the direct comparison to 
 the commonly used Yeh-Berkowitz method that this enables. Here it is found
  that naive application of the latter leads to physically unreasonable res
 ults\, and greatly influences the structure of water in the contact layer.
  This work should therefore be of general importance to those studying pol
 ar/charged surfaces in aqueous environments. I will also highlight recent 
 work that uses the finite field methods to understand the response of bulk
  electrolyte solutions to imposed electric and electric displacement field
 s.
LOCATION:Department of Chemistry\, Cambridge\, Unilever lecture theatre
END:VEVENT
END:VCALENDAR