THE FERROMAGNETIC COUPLING MECHANISM IN METALLOCENIUM PI-ANION STACKSAS SEEN BY NMR-SPECTROSCOPY

Authors
BLUMEL J HEBENDANZ N HUDECZEK P KOHLER FH STECK A STRAUSS W
Citation
J. Blumel et al., THE FERROMAGNETIC COUPLING MECHANISM IN METALLOCENIUM PI-ANION STACKSAS SEEN BY NMR-SPECTROSCOPY, Molecular crystals and liquid crystals science and technology. Section A, Molecular crystals and liquid crystals, 232, 1993, pp. 513-519
Citations number
19
Categorie Soggetti
Crystallography
Journal title
Molecular crystals and liquid crystals science and technology. Section A, Molecular crystals and liquid crystals → ACNP
ISSN journal
1058725X
Volume
232
Year of publication
1993
Pages
513 - 519
Database
ISI
SICI code
1058-725X(1993)232:<513:TFCMIM>2.0.ZU;2-O
Abstract
The H-1 and C-13 NMR spectra of selected nickelocenium, chromocenium, and ferrocenium ions are reported. The sign of the signal shifts estab lishes positive or negative electron spin on the ligand for Ni or Cr s andwiches, respectively. Hyperconjugative spin transfer to beta carbon atoms of substituted ferrocenium ions is used to prove negative spin on their ligands. For (Cp)Cr(arene) derivatives negative spin on the ligand is indicated by characteristic shifts of the beta-proton signal s. The results meet the requirements of the mechanism of Kahn and Koll mar 5b,c for magnetic intra-stack interactions.