Analysis of the second harmonic generation signal from a liquid/air and liquid/liquid interface

作者:Pham Thanh Tung; Jonchere Alban; Dufreche Jean Francois; Brevet Pierre Francois; Diat Olivier*
来源:Journal of Chemical Physics, 2017, 146(14): 144701.
DOI:10.1063/1.4979879

摘要

Three different liquid interfaces, water/air, thiophene/air, and water/thiophene, were probed using the second harmonic generation (SHG) technique. Thiophene and water have been chosen because the hyperpolarizability of these molecules has already been measured or calculated and the different values can be found in literature. We have studied the microscopic structure of these interfaces by comparing the components of the second order susceptibility tensor determined from the SHG polarization curve analysis with those determined via a molecular dynamics (MD) simulation of these interfaces. We have indeed computed the structure and orientation of water and thiophene molecules at the liquid/air and liquid/liquid (L/L) interfaces as a function of the distance from the interface. The integrated susceptibility values calculated by MD simulations agree well with SHG results and validate the choice of force fields that should permit to quantify more complex L/L interfaces. Published by AIP Publishing.

  • 出版日期2017-4-14
  • 单位中国地震局