Raman spectra of L-leucine crystals

TL;DR

This study investigates the Raman spectra of L-leucine crystals across a temperature range, identifying spectral changes and evidence of a structural phase transition at high temperatures.

Contribution

It provides the first detailed Raman spectral analysis of L-leucine crystals and reports on temperature-induced spectral modifications indicating a phase transition.

Findings

Spectral bands assigned to specific molecular vibrations.

Observation of spectral modifications around 353 K.

Evidence of a structural phase transition in L-leucine.

Abstract

Single crystal samples of L-leucine, C6H13NO2, a fundamental aliphatic amino acid of the human body, have been studied by Raman spectroscopy at temperatures from 300 to 430 K over the spectral range from 50 to 3100 cm-1. A tentative assignment of all bands is given. For high temperatures, several modifications on the Raman spectra were observed at about 353 K, giving evidence that the L-leucine crystal undergoes a structural phase transition.