The behaviour of the

Tetrahedrally coordinated copper(I) complexes C11L4X have been synthesized, L being P(OR)3, PR3 or P(R)n(OR)3-n, and X being a non-coordinating anion such as Perchlorate or tetrafluoroborate. Depending on the nature of the bound phosphorus ligand the Cu(I) complexes give well resolved 63 Cu NMR spectra including a quintet signal due to spin-spin coupling between 63 Cu and 31 P. The 63 Cu NMR spectra have been analyzed with reference to the chemical shift (), the shielding constant a* (given on an absolute atomic scale), the linewidth Av, and the coupling constant J( 63 Cu-31 P). Generally, the relative magnitude of these NMR parameters are in satisfactory agreement with results reported for isoelectronic Ni(O) complexes with the phosphorus ligands mentioned above. Furthermore, the NMR properties of the Cu(I) compounds are discussed in terms of cr-donor or 7r-acceptor capacities of the ligands coordinated, and stereochemical properties of the complexes.

In a Mo(CO)6 powder sample the 95Mo NMR signal has been observed using a FT pulse spectrometer at magnetic fields of 2.11 T and 2.24 T. A second-order quadrupole splitting has been found. The quadrupole coupling constant is (21.1_+2.3) kHz, the asymmetry parameter is less than 0.1. It is shown, that the second-order quadrupole splitting is affected by low-speed sample spinning. Theoretical and experimental spectra are given.

By Fourier transform NMR spectroscopy the

The NMR signals of