Femtosecond response in rare gas matrices doped with NO impurities: A stochastic approach

TL;DR

This paper models the femtosecond electronic response of NO molecules in rare gas matrices using a stochastic Langevin approach, successfully matching experimental data and providing insights into the relaxation dynamics of such systems.

Contribution

It introduces a simple damped harmonic oscillator model within a stochastic framework to describe femtosecond responses in doped rare gas matrices, offering a new analytical tool.

Findings

The model accurately reproduces absorption and emission line shapes.

The approach captures the matrix's first-solvation shell response.

Good agreement with experimental data supports the model's validity.

Abstract

The femtosecond response of NO-doped rare gas matrices is studied within a stochastic Langevin theoretical framework. As is shown, a simple damped harmonic oscillator model can describe properly the absorption and emission line shapes associated with the NO ($A^2\Sigma^+ \longleftrightarrow X^2\Pi$) electronic transitions inside these media as well as the matrix first-solvation shell response in a process with two timescales, finding a fairly good agreement with available experimental data. This approach thus constitutes an alternative and complementary way to analyze the structural relaxation dynamics of systems in liquids and solids, leading to a better understanding of the underlying physics.