Theoretical models of high-harmonic generation in binary solutions

Recent experimental results have shown [Proc. Natl. Acad. Sci. U.S.A. 122 (48) e2514825122] the suppression of a single harmonic in the high-harmonic spectrum of a binary solution of fluorobenzene (PhF) and methanol (MeOH). Previous theoretical results in 1D have explained the suppression behavior with the use of a scattering barrier mimicking the hydrogen bond formed upon solution of PhF into MeOH. In this work, we extend our theoretical studies with numerical solutions to the 2D time-dependent Schrödinger equation. By varying the parameters such as shape, size, and location of the obstruction, we resolve any dependencies affecting the harmonic spectrum and find that results are in good agreement with the 1D case. Guided by our 2D results, we then continue our studies with a more realistic, two molecule system using time-dependent density functional theory calculations. Our results further solidify that the local structure of the liquid is playing a key role, and show that high-harmonic generation could be a useful tool in resolving liquid phase structure and dynamics.