PHASE-DIAGRAM OF (LA1-XNDX)(3)S-4 SOLUTIO NS SINGULARITIES

Superconducting and magnetic phase diagrams of (La1-xNdx)(3)S-4 solid solutions are investigated in the concentration range from 0 to 15 at% Nd. The superconductivity is observed at x = 6 at% Nd, exceeding the critical concentration value x(c) = 4 at%, followed from Abrikosov-Gor 'kov theory. A weaker suppression of the superconductivity appears to be due to the Nd3+ ground term splitting by the crystalline field. It follows from the magnetic susceptibility measurement that the splittin g by the crystalline field is 75 +/- 3 K. At concentration x > 6 at% N d one can observe magnetic transitions to a ferromagnetic state.