  We study the physical properties of three clusters of galaxies, selected from
a BeppoSAX Wide Field Camera (WFC) survey. These sources are identified as 1RXS
J153934.7-833535, 1RXS J160147.6-754507, and 1RXS J081232.3-571423 in the ROSAT
All-Sky Survey catalogue. We obtained XMM-Newton follow-up observations for
these three clusters. We fit single and multi-temperature models to spectra
obtained from the EPIC-pn camera to determine the temperature, the chemical
composition of the gas and their radial distribution. Since two observations
are contaminated by a high soft-proton background, we develop a new method to
estimate the effect of this background on the data. For the first time, we
present the temperature and iron abundance of two of these three clusters. The
iron abundance of 1RXS J153934.7-33535 decreases with radius. The fits to the
XMM-Newton and Chandra data show that the radial temperature profile within 3'
towards the centre either flattens or lowers. A Chandra image of the source
suggests the presence of X-ray cavities. The gas properties in 1RXS
J160147.6-754507 are consistent with a flat radial distribution of iron and
temperature within 2' from the centre. 1RXS J081232.3-571423 is a relatively
cool cluster with a temperature of about 3 keV. The radial temperature and iron
profiles suggest that 1RXS J153934.7-833535 is a cool core cluster. The Chandra
image shows substructure which points toward AGN feedback in the core. The flat
radial profiles of the temperature and iron abundance in 1RXS J160147.6-754507
are similar to the profiles of non-cool-core clusters.
