Density data for dilute aqueous solutions of nitrobenzene and three isomeric nitrophenols (2-, 3-, or 4-nitro-1-hydroxybenzene) are presented together with partial molar volumes at infinite dilution calculated from the experimental data. The measurements were performed at T = 298.15 K up to either T = 573.15 K (nitrobenzene, m-nitrophenol) or T = 548.15 K (p-nitrophenol) or T = 523.15 K (o-nitrophenol) and at either atmospheric pressure, or at pressures close to the saturated vapor pressure of water, and also at p = 30 MPa. The data were obtained using a high-temperature high-pressure flow vibrating-tube densimeter for measurements at elevated pressures and a commercial vibrating-tube cell DMA 602HT for measurements at atmospheric pressure. (C) 2003 Elsevier Science Ltd. All rights reserved.