13C NMR investigation of the superconductor MgCNi3 up to 800 K

The first ¹³C NMR measurements in MgCNi3 was carried out. It was found that the strong temperature dependence of ¹³K and a¹³T2T and subsequent saturation below ∼50 and ∼20 K are consistent with the presence of modest electronic correlation effects.