TY - JOUR
T1 - Local density augmentation in neat supercritical fluids
T2 - The role of electrostatic interactions
AU - Song, W.
AU - Maroncelli, M.
N1 - Funding Information:
The authors thank Ken-ichi Saitow for helpful discussions of his work. The present study was funded by a grant from the National Science Foundation (CHE-9980383).
PY - 2003/9/5
Y1 - 2003/9/5
N2 - 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.
AB - 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.
UR - http://www.scopus.com/inward/record.url?scp=0141786691&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0141786691&partnerID=8YFLogxK
U2 - 10.1016/j.cplett.2003.07.003
DO - 10.1016/j.cplett.2003.07.003
M3 - Article
AN - SCOPUS:0141786691
SN - 0009-2614
VL - 378
SP - 410
EP - 419
JO - Chemical Physics Letters
JF - Chemical Physics Letters
IS - 3-4
ER -