Contribution a l'etude structurale des phases V1-xCrxO2

The authors have determined the phase diagram of the system V_1?xCr_xO₂ (0 ? x ? 0.15) by magnetic susceptibility, D. T. A. and X-ray diffraction measurements. At small chromium concentrations the existence of the intermediate phases M₂ and M₃, between M₁ and the rutile phase, has been confirmed. But it has been found that M₃ has actually a triclinic symmetry without destruction of the V-V pairs already existing in M₁. At higher concentrations (x > 0.07) there appears a monoclinic M₄ phase in which the V - V pairs are all destroyed.