A time correlation function theory describing static field enhanced third order optical effects at interfaces.

Christine Neipert; Brian Space

doi:10.1063/1.2397687

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A time correlation function theory describing static field enhanced third order optical effects at interfaces.

Christine Neipert·Brian Space

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Abstract

Sum vibrational frequency spectroscopy, a second order optical process, is interface specific in the dipole approximation. At charged interfaces, there exists a static field, and as a direct consequence, the experimentally detected signal is a combination of enhanced second and static field induced third order contributions. There is significant evidence in the literature of the importance/relative magnitude of this third order contribution, but no previous molecularly detailed approach existed to separately calculate the second and third order contributions. Thus, for the first time, a molecularly detailed time correlation function theory is derived here that allows for the second and third order contributions to sum frequency vibrational spectra to be individually determined. Further, a practical, molecular dynamics based, implementation procedure for the derived correlation functions that describe the third order phenomenon is also presented. This approach includes a novel generalization of point atomic polarizability models to calculate the hyperpolarizability of a molecular system. The full system hyperpolarizability appears in the time correlation functions responsible for third order contributions in the presence of a static field.

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Computer Simulation Models, Chemical Models, Molecular Optics and Photonics Static Electricity Statistics as Topic Surface Properties Time Factors Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.

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Christine Neipert, Brian Space. 2006-12-14. A time correlation function theory describing static field enhanced third order optical effects at interfaces.. https://doi.org/10.1063/1.2397687

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