Main Title |
Cobalt-59 Nuclear Magnetic Resonance Studies of Chloro-, Bromo-, and Iodo-Substituted Tris(acetylacetonato)cobalt(III) Complexes. |
Author |
Busse, S. C. ;
Abbott, E. H. ;
|
CORP Author |
New Mexico Univ., Albuquerque. School of Medicine. ;Montana State Univ., Bozeman. Dept. of Chemistry.;Environmental Research Lab.-Duluth, MN.;National Science Foundation, Washington, DC. |
Publisher |
c1989 |
Year Published |
1989 |
Report Number |
EPA-R-809478 ;NSF-CHE78-26160; EPA/600/J-89/013; |
Stock Number |
PB89-236343 |
Additional Subjects |
Cobalt isotopes ;
Nuclear magnetic resonance ;
Relaxation time ;
Cobalt halides ;
Electrostatics ;
Ligands ;
Temperature ;
Chelates ;
|
Holdings |
Library |
Call Number |
Additional Info |
Location |
Last Modified |
Checkout Status |
NTIS |
PB89-236343 |
Some EPA libraries have a fiche copy filed under the call number shown. |
|
07/26/2022 |
|
Collation |
6p |
Abstract |
The cobalt-59 nuclear magnetic resonance spectra and longitudinal relaxation times have been studied for tris(acetylacetonato)cobalt(III) complexes with chloride, bromide, and iodide substitution at the methine carbon atom of the chelate ring. The cobalt-59 chemical shift is sufficiently sensitive to this remote substitution that cobalt-59 resonances are well resolved for each complex in a series of monohalo-, dihalo-, and trihalo-substituted complexes. The chemical shift is not linearly dependent on substitution. For the more electronegative halides, chlorine and bromine, static electric field gradient effects can be observed in the mixed-ligand complexes, but these effects amount to less than 10% of the observed relaxation rate. Through comparison of carbon-13 and cobalt-59 relaxation times it appears that in the solvents benzene, diglyme, and acetone, the cobalt-59 relaxation is a consequence of rotational reorientation, but for the solvent chloroform the cobalt-59 relaxation is different. Several possible explanations for this observation are considered. (Copyright (c) 1989 by the American Chemical Society and reprinted by permission of the copyright owner.) |
Supplementary Notes |
Pub. in Inorganic Chemistry, v28 n3 p488-491 1989. Prepared in cooperation with Montana State Univ., Bozeman. Dept. of Chemistry. Sponsored by Environmental Research Lab.-Duluth, MN., and National Science Foundation, Washington, DC. |
NTIS Title Notes |
Journal article. |
Category Codes |
77B; 99F |
NTIS Prices |
PC A02/MF A01 |
Primary Description |
600/03 |
Document Type |
NT |
Cataloging Source |
NTIS/MT |
Control Number |
931317647 |
Origin |
NTIS |
Type |
CAT |