Motivated by a recent study of Saitow et al. [Chem. Phys. Lett. 368 (2003) 209-214 ], computer simulations and dielectric analyses are used to explore the effect electrical interactions have on density augmentation in supercritical fluoroform. Simulations of 2-site models of fluoroform and ethane show that electrical interactions increase local densities but not dramatically. The density augmentation simulated in both fluids (Δρ max=0.12ρc and 0.15ρc) is much smaller than the value Δρmax≅0.5ρc deduced by Saitow et al. from Raman measurements. This discrepancy can be reconciled if the observed vibrational shifts reflect mainly dipolar interactions, an interpretation justified by ab initio calculations.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry