Binary diffusion coefficients at infinite dilution in supercritical carbon dioxide, DAB, have been measured for the jour monohalogenated benzenes (fluorobenzene, chlorobenzene, bromobenzene, and iodobenzene) with the Taylor-Aris technique in a chromatographic apparatus as a function of temperature and pressure. The ranges covered for these two variables were 313-333 K and 15.0-35.0 MPa, respectively. As the four solutes are similar molecules, the corresponding states principle (CSP) has been tested, together with the results of several predictive equations. (c) 2007 American Institute of Chemical Engineers AIChE J, 53: 3054-3061, 2007.