The DTA method. hi combination with the calculation-experimental crite
ria, is used for constructing phase diagrams ol the binary systems Li
- (La. Ce. Pr, Nd. Pm, Sm) which are specified by the limited solubili
ty of the components in the liquid and in the solid states. Correlatio
n is established between the coordinates of the eutectic and monotecti
c transformations and the REM nucleus charge.