C-13 NUCLEAR-MAGNETIC-RESONANCE OF TRANSITION-METAL CARBONYL CLUSTERSTHROUGH INTERMOLECULAR CROSS-POLARIZATION TRANSFER IN THE SOLID-STATE

The C-13 cross polarisation magic angle spinning NMR spectra of [Ni-6( CO)(12)](2-) at natural C-13 abundance have been recorded with four di fferent cations, [NMe(4)](+), [NEt(4)](+), [AsPh(4)](+) and [N(PPh(3)) (2)](+) and the crystal structure of the previously unreported [AsPh(4 )](+) salt of [Ni-6(CO)(12)](2-) has been determined. Carbonyl resonan ces of the anion at natural (CO)-C-13 abundance with excellent signal- to-noise ratio (ca. 1:1 for a single scan) are only observed for [NMe( 4)](2)[Ni-6(CO)(12)] and the possible reasons for this are discussed.