The setup comprised a dual Ti:sapphire amplifier (Thales Laser), synchronised by a single oscillator seed source (Femto Laser), producing two 800 nm, 10 kHz, 0.8 mJ beams with FWHM pulse durations and bandwidths of 1 ps, 20 cm -1 (𝛼 ) and 50 fs, 300 cm -1 (𝛽 ). Optical parametric amplifiers (4W pump power, Light Conversion TOPAS) were used to tune the central frequency of the beams: 𝜔 𝛼 was varied from 1250-1750 cm -1 in step sizes of 5 cm -1 , and 𝜔 𝛽 was set to 3200 cm -1 . The 𝛾 beam was produced by running an arm of the fs beam through an etalon, producing 800 nm, 1 ps pulses with a bandwidth of 12 cm -1 . All three beams were focused on the sample in a geometry that satisfied phase matching conditions. Time delays between each pulse were created using delay stages, and were set to 𝑇 𝛼𝛽 = 𝑇 𝛽𝛾 = 0.4 ps. The FWM signal was detected by a combination of a spectrograph and a charge coupled device camera.