In Situ Raman Spectroscopic Studies of Liquid Carbon Tetrachloride (CCl₄) Under Static and Laser-Driven Shock...

Area of Science:

• Materials Science
• Condensed Matter Physics
• Spectroscopy

Background:

• Carbon tetrachloride (CCl4) is a molecule with significant applications in various industrial processes.
• Understanding its behavior under high pressure is crucial for predicting its properties in extreme environments.
• Raman spectroscopy is a powerful technique for probing molecular vibrations and phase transitions.

Purpose of the Study:

• To investigate the high-pressure behavior of carbon tetrachloride (CCl4) using Raman scattering.
• To compare the effects of static and dynamic compression on CCl4.
• To determine the mode Gruneisen parameters for CCl4 under pressure.

Main Methods:

• High-pressure Raman scattering experiments were conducted using a diamond anvil cell (DAC) for static compression.
• Laser-driven shock compression experiments were performed using a glass-confined target geometry.
• Time-resolved Raman spectroscopy (TRRS) was employed to study dynamic compression effects.

Main Results:

• The symmetric stretching mode (ν1), symmetric bending mode (ν2), and asymmetric bending mode (ν4) of CCl4 exhibited pressure-induced blueshifts.
• Mode Gruneisen parameters were successfully determined for the observed Raman modes.
• Shock velocities derived from Raman signals aligned with hydrodynamic simulations.

Conclusions:

• Both static and dynamic compressions induce significant changes in the vibrational spectra of CCl4.
• The determined mode Gruneisen parameters offer quantitative insights into the anharmonicity of CCl4 vibrations.
• The study validates the use of TRRS for probing shock-compressed materials.