TRINUCLEAR NICKEL CLUSTERS, [NI-3(MU(3)-L)(MU(3)-I)(MU(2)-DPPM)3](N+) (L=I-, CO, CNCH3, CN-2,6-ME(2)C(6)H(3), CN-I-C3H7, CN-T-C4H9, CN-N-C4H9, NO+) AND THE DIMER OF TRIMER HEXANUCLEAR NICKEL CLUSTERS ([NI-3(MU(3)-I)(MU(2)-DPPM)(3)](2)(MU(3),MU(3'),ET

摘要

The mass spectra of a series of trinuclear nickel clusters of the general formula [Ni-3(mu(3)-L)(mu(3)-I)(mu(2)-dPPm)(3)](n+), where L = I- (1), CO (2), CNCH3 (3), CN-2,6-Me(2)C(6)H(3) (4), CN-i-C3H7 (5), CN-t-C4H9 (6), CN-n-C4H9 (7), and NO+ (8) and n = 0, 1, 2 were measured by Plasma Desorption (PD) and Fast Atom Bombardment (FAB) mass spectrometry. Strong molecular ion peaks were observed for all of the trinuclear clusters except 8 by both techniques. Ion fragmentation followed similar pathways in both ionization modes. Dimers of trinuclear clusters, {[Ni-3(mu(3)-I)(mu(2)-dppm)(3)](2)(mu(3),mu(3'),eta(1) eta(1')-CN-R-NC)}(2+) where R = -(CH2)(6-) (9) and 1,4-C6H4 (10) were prepared by the reaction of two equivalents of 1 with one equivalent of the appropriate diisocyanide, CN-R-NC. Clusters 9 and 10 were not distinguishable from simple trimers such as 3-7 by P-31 NMR and optical spectroscopies, but were unambiguously identified by PD and FAB mass spectrometry. The parent ions are different for the two techniques: MI(+) in the former case and M(+) in the latter. [References: 44]