ELECTRONIC-PROPERTIES OF PT0.75(MN1-XCRX)0.25 ALLOYS

The dependence of the electronic density of states at the Fermi level on the concentration of Mn and Cr in Pt1-xMnx, Pt1-xCrx and Pt0.75(Mn1 -xCrx)0.25 alloys is studied. The electronic density of states is calc ulated using the TB LMTO-CPA method. We observe the increasing electro nic specific heat coefficient, gamma, with increase in the chromium co ncentration in the ferromagnetic Pt0.75(Mn1-xCrx)0.25 alloys. The decr ease in the gamma coefficient for x > 0.7 can be explained by assuming a cosine-type dependence of the local magnetic moment on the Pt atom in the region of Cr concentration 0.7 < x < 1.0.