Spectral shapes of solid neon

TL;DR

This study uses Path Integral Monte Carlo to analyze the spectral shapes of solid neon, highlighting quantum effects on phonon spectral features and reconstructing spectra through continued fraction expansion.

Contribution

It introduces a quantum Monte Carlo approach to compute spectral moments of solid neon and discusses the impact of quantum effects on spectral line shapes.

Findings

Quantum effects significantly influence spectral peak positions.

Spectral line-widths are affected by quantum fluctuations.

Effective potential methods provide useful approximations.

Abstract

We present a Path Integral Monte Carlo calculation of the first three moments of the displacement-displacement correlation functions of solid neon at different temperatures for longitudinal and transverse phonon modes. The Lennard-Jones potential is considered. The relevance of the quantum effects on the frequency position of the peak and principally on the line-width of the spectral shape is clearly pointed out. The spectrum is reconstructed via a continued fraction expansion; the approximations introduced using the effective potential quantum molecular dynamics are discussed.