Abstract: Some powder samples of molybdemum-copper-sulpher dimetal cluster containing=CuX form ligands, where X represents halogen, were studied by MASNMR method. The lines obtained were assigned and the effects of=CuX ligands on the positions of various lines were discussed. Comparisons between the ¹³C spectra of three crystalline powder, (t-BuNC)₄ Mo(t-BuS)₂, (t-BuNC)₄ Mo (μ-t-BuS)₂CuX and (t-BuNC)₄ Mo(μ-t-BuS) (μ-CO)CuX, were made. A simple but successful way to perform an inves tigation when the powder sample to be studied was not sufficient was also proposed.

Key words: culster, magic angle spinning (MAS), delocalization