Measurement of Raman χ(3) and Theoretical Estimation of DOVE Four Wave Mixing of Hydrogen Peroxide

Hydrogen peroxide has strong infrared (IR) transitions nu(6) and its combination band nu(2)+nu(6), which may provide a unique opportunity to implement doubly vibrationally enhanced (DOVE) four wave mixing (FWM) for directly measuring hydrogen peroxide in spectrally overcrowded mixtures. In this work, the magnitude of the DOVE third-order susceptibility chi((3)) was theoretically estimated. By using a FWM interferometric method, one of the strongest Raman bands, O-O stretch nu(3) Raman chi((3)) of 30 wt % H2O2, was first measured to be 1.2 x 10(-14) esu. The Raman chi((3)) of nu(2) was then determined to be 5.3 x 10(-15) esu based on their relative Raman intensities. The resulting Raman chi((3)) of nu(2) was used to calculate the DOVE chi((3)) of (nu(6), nu(2)+nu(6)), together with the dipolar moments of the two IR transitions determined from IR absorption measurement. The calculated value of DOVE-IR chi((3)) was 1.1 x 10(-13) esu for pure H2O2, about 1.5 times larger than that of the strong ring breathing Raman band of benzene. The large DOVE x(3) suggests the feasibility of direct measurement of hydrogen peroxide in an aqueous environment using DOVE four wave mixing.