X-ray investigations of the intermetallic phases CaCdsub(1-x)Tlsub(x) and CaInsub(1-x)Tlsub(x) and Knight shift measurements of 205Tl- and 113Cd-NMR in the system CaCdsub(1-x)Tlsub(x)

The quasibinary systems CaCd 1-x Tl x and CaIn 1-x Tl x - form continuous series of solid solutions for all concentrations x: 0 ≦ x ≦ 1. All alloys of both systems crystallize with space group Oh 1 -PmSm and one formula unit per unit cell (CsCl-type structure). Considerable deviations from Vegard's law occur for CaCd 1-x Tl x, while they are negligible for CaIn 1-x Tl x . No sign for the appearance of superstructures was found in either system after equilibrating them at 300 °C for two hours. In the system CaCd 1-x Tl x the Knight shift K s of the 205 Tl- and 113 Cd-NMR was measured at room temperature as a function of x. Saturated Tl(CH 3 CO 2 )- and Cd(NO 3 ) 2 solutions served as reference samples. The Knight shift of the 205 Tl-resonance increases remarkably with increasing concentration x, whereas the Knight shift of the 113 Cd-NMR decreases slightly with increasing x. No simple qualitative explanation is found for K s (Tl) =f(x) and K s (Cd) =f(x)