. The resulting "echo" peak reveals the true, unblurred homogeneous line shape underneath. 6. Practical Applications What It Measures Practical Benefit χ(3)chi raised to the open paren 3 close paren power Excited state lifetimes and kinetics. Tracks energy transfer in solar cells. Sum Frequency Generation (SFG) χ(2)chi raised to the open paren 2 close paren power Vibrational spectra exclusively at interfaces. Proves molecular orientation at water/oil boundaries. 2D Infrared (2D IR) χ(3)chi raised to the open paren 3 close paren power Vibrational coupling and structural evolution. Maps structural changes in proteins in real-time. Coherent Anti-Stokes Raman (CARS) χ(3)chi raised to the open paren 3 close paren power Chemical-specific vibrational imaging. Allows high-speed biological imaging without dyes. Summary for the Practitioner
In his classic textbook, "Principles of Nonlinear Optical Spectroscopy," Shaul Mukamel provides a comprehensive and practical approach to understanding the principles of nonlinear optical spectroscopy. Mukamel's approach focuses on the use of nonlinear optical techniques to study the dynamics of molecular systems, rather than on the technical details of the experimental methods. Proves molecular orientation at water/oil boundaries
To understand nonlinear spectroscopy, it helps to first look at linear spectroscopy. Linear Spectroscopy "Principles of Nonlinear Optical Spectroscopy