Abstract
Temperature dependencies of Raman linewidths of the two polarized modes in have been determined along the coexistence line with mK resolution. Comparing the neat fluid with diluted states of in Xe (and ), quite opposite behaviors of have been observed when the liquids approach their respective critical temperatures : While the mixture shows the well known -shaped effect of critical broadening, a unique and sharp density-correlated line narrowing has been observed in the neat state. The gradual switchoff of intermolecular resonance couplings with decreasing density is responsible for this narrowing phenomenon.
- Received 20 February 1996
DOI:https://doi.org/10.1103/PhysRevLett.77.2746
©1996 American Physical Society