Testing the ab initio quantum‐scattering calculations for the D₂–He benchmark system with stimulated Raman spectroscopy

Abstract

This work presents a comparison between experimental and calculated values for the collisional line broadenings and shifts of the S0(0), S0(1), and S0(2) lines of the rotational Raman spectrum of D2 perturbed by He at 77, 195, and 300 K. The pure rotational Raman spectra were obtained by means of a stimulated Raman spectroscopy experimental setup. Close coupling dynamical calculations were performed on the most recent ab initio H2–He potential energy surface. The resulting scattering matrix elements implemented in the general Hess method allow us to provide pressure broadening, pressure shifting, and Dicke coefficients from 10 to 400 K. Experimental and calculated values agree well with each other.

Accurate wavenumber measurements for the S0(0), S0(1), and S0(2) pure rotational Raman lines of D2

“…This is critical to reach the relatively low frequencies of the rotational lines to be studied. A detailed description of the modified setup can be found in the parent article mentioned in the introduction …”

“…There is, however, a conspicuous absence of purely rotational data, with the most accurate measurements of the rotational Raman spectrum of these molecules dating back over 30 years. This inspired the measurements presented in this article, which were conducted in the course of a larger experimental work whose aim was the determination of broadening and shift coefficients in D 2 and that was already in the process of being published …”

“…This inspired the measurements presented in this article, which were conducted in the course of a larger experimental work whose aim was the determination of broadening and shift coefficients in D 2 and that was already in the process of being published. [18] apparatus is a quasi-continuous (cw) SRS setup, whose basic configuration has already been described in detail in a number of prior articles. [19,20] The configuration was modified for these experiments so that the pump and probe beams could operate at frequencies close to each other and also with polarizations perpendicular to each other.…”

Recent advances in linear and nonlinear Raman spectroscopy. Part XIII

“…Martinez et al tested ab initio quantum scattering calculations for the D 2 –He benchmark system with SRS. Close coupling dynamical calculations were performed on the most recent ab initio D 2 –He potential energy surface . Zada and co‐workers used SRS microscopy for fast microplastics identification.…”

“…Close coupling dynamical calculations were performed on the most recent ab initio D 2 -He potential energy surface. [121] Zada and co-workers used SRS microscopy for fast microplastics identification. They conclude that SRS can be an efficient method for monitoring microplastics in the environment and potentially many other matrixes of interest.…”