  Neutron diffraction technique was used to study distribution of Co and Cr
atoms over different lattice sites as well as lattice paramaters in sigma-phase
Co100-xCrx compounds with x = 57.0, 62.7 and 65.8. From the diffractograms
recorded in the temperature range of 4.2 - 300 K it was found that all five
sites A, B, C, D and E are populated by both kinds of atoms. Sites A and D are
predominantly occupied by Co atoms while sites B, C and E by Cr atoms. The unit
cell parameters a and c, hence the unit cell volume, increase with x, the
increase being characteristic of the lattice paramater and temperature. Both a
and c show a non-linear increase with temperature.
