Abstract:
:The floating water bridge phenomenon is a freestanding rope-shaped connection of pure liquid water, formed under the influence of a high potential difference (approximately 15 kV). Several recent spectroscopic, optical, and neutron scattering studies have suggested that the origin of the bridge is associated with the formation of anisotropic chains of water molecules in the liquid. In this work, high energy X-ray diffraction experiments have been performed on a series of floating water bridges as a function of applied voltage, bridge length, and position within the bridge. The two-dimensional X-ray scattering data showed no direction-dependence, indicating that the bulk water molecules do not exhibit any significant preferred orientation along the electric field. The only structural changes observed were those due to heating, and these effects were found to be the same as for bulk water. These X-ray scattering measurements are supported by molecular dynamics (MD) simulations which were performed under electric fields of 10(6) V/m and 10(9) V/m. Directional structure factor calculations were made from these simulations parallel and perpendicular to the E-field. The 10(6) V/m model showed no significant directional-dependence (anisotropy) in the structure factors. The 10(9) V/m model however, contained molecules aligned by the E-field, and had significant structural anisotropy.
journal_name
Proc Natl Acad Sci U S Aauthors
Skinner LB,Benmore CJ,Shyam B,Weber JK,Parise JBdoi
10.1073/pnas.1210732109subject
Has Abstractpub_date
2012-10-09 00:00:00pages
16463-8issue
41eissn
0027-8424issn
1091-6490pii
1210732109journal_volume
109pub_type
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