Context :

Aims : This work presents a uniform and homogeneous study of chemical abundances of refractory elements in 101 stars with and 94 without known planetary companions .
We carry out an in-depth investigation of the abundances of Si , Ca , Sc , Ti , V , Cr , Mn , Co , Ni , Na , Mg and Al .
The new comparison sample , spanning the metallicity range -0.70 < [ Fe / H ] < 0.50 , fills the gap that previously existed , mainly at high metallicities , in the number of stars without known planets .

Methods : We used an enlarged set of data including new observations , especially for the field “ single ” comparison stars .
The line list previously studied by other authors was improved : on average we analysed 90 spectral lines in every spectrum and carefully measured more than 16 600 equivalent widths ( EW ) to calculate the abundances .

Results : We investigate possible differences between the chemical abundances of the two groups of stars , both with and without planets .
The results are globally comparable to those obtained by other authors , and in most cases the abundance trends of planet-host stars are very similar to those of the comparison sample .

Conclusions : This work represents a step towards the comprehension of recently discovered planetary systems .
These results could also be useful for verifying galactic models at high metallicities and consequently improve our knowledge of stellar nucleosynthesis and galactic chemical evolution .