The density of two binary mixtures formed by 1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF6] with aromatic compound (benzyl alcohol or benzaldehyde) has been determined over the full range of compositions Lit the temperature range from 298.15 K to 313.15 K and at atmospheric pressure using a vibrating-tube densimeter (DMA4500). Excess molar volumes (V-m(E)) have been obtained from these experimental results, and been fitted by the fourth-order Redlich-Kister equation. Our results show V-m(E) decreases slightly when temperature increases in the systems studied. The results have been interpreted in terms of ion-dipole interactions and structural factors of the ionic liquid and these organic molecular liquids. (c) 2006 Elsevier Ltd. All rights reserved.