Determination of the Coupling Coefficient C(\nu) from the Calculations of the Low-frequency Raman Spectrum in PMMA

TL;DR

This paper calculates the low-frequency Raman spectrum of PMMA using atom-atom potentials, accounting for anharmonicity and disorder, to determine the coupling coefficient C(ν) relevant for understanding molecular vibrations.

Contribution

It introduces a method to compute the coupling coefficient C(ν) from Raman spectra considering anharmonicity and disorder effects in PMMA.

Findings

Calculated low-frequency Raman spectra for PMMA.

Derived the coupling coefficient C(ν) from spectral data.

Accounted for anharmonicity and disorder in the model.

Abstract

Using the atom-atom potentials method, we have calculated the low-frequency Raman spectra of molecular crystal model with elements of disorder (Poly-Methyl-Methacrylate) PMMA that has a flexible molecule. Based on the results the coupling factor C(\nu) has been calculated. Anharmonicity of vibrations, electro-optical anharmonicity, and disorder were taken into account.