Cyclopentadienyl bonding in bis(cyclopentadienyl)neptunium(IV) compounds from /sup 237/Np Moessbauer spectra

Journal Article · Wed Feb 02 04:00:00 EST 1983 · Inorg. Chem.; (United States)

DOI:https://doi.org/10.1021/ic00145a026· OSTI ID:6163217

Karraker, D G

/sup 237/Np Moessbauer spectra were measured for a series of Np(IV) compounds of the general compositions NpX/sub 4/, NpX/sub 2/Y/sub 2/, and NpX/sub 2/YY' (X = acac, bis(1-pyrazolyl)borate, tris(1-pyrazolyl)borate; Y, Y' = Cl, Cp, MeCp). Comparison of the isomer shifts of the Moessbauer spectra showed no evidence for covalent bonding between the Cp ligand and Np(IV) in the Cp/sub 2/Np/sup IV/ and CpNp/sup IV/ moieties. It is proposed that ligand repulsion in NpX/sub 2/-Cp/sub 2/ and NpX/sub 2/(MeCp)/sub 2/ compounds lengthens the Np(IV)-Cp and Np(IV)-(MeCp) bonds and thus prevents any appreciable Np(IV)-ligand orbital overlap. Moessbauer magnetic splitting and quadrupole splitting parameters are greater for (tris(1-pyrazolyl)borato)neptunium(IV) compounds than for (bis(1-pyrazolyl)borato)neptunium(IV) compounds, a result attributed to the stronger field from the tridentate coordination of the tris(1-pyrazolyl)borate ligand.

• Research Organization: Savannah River Lab., Aiken, SC
• DOE Contract Number: AC09-76SR00001
• OSTI ID: 6163217
• Journal Information: Inorg. Chem.; (United States), Journal Name: Inorg. Chem.; (United States) Journal Issue: 3 Vol. 22:3; ISSN INOCA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400702* -- Radiochemistry & Nuclear Chemistry-- Properties of Radioactive Materials
ACTINIDE COMPLEXES
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALKENES
ALPHA DECAY RADIOISOTOPES
CHEMICAL BONDS
CHLORINE
COMPARATIVE EVALUATIONS
COMPLEXES
CYCLOALKENES
CYCLOPENTADIENE
DIENES
ELEMENTS
GAMMA SPECTRA
HALOGENS
HEAVY NUCLEI
HETEROCYCLIC COMPOUNDS
HYDROCARBONS
ISOMER SHIFT
ISOTOPES
LIGANDS
MOESSBAUER EFFECT
NEPTUNIUM 237
NEPTUNIUM COMPLEXES
NEPTUNIUM ISOTOPES
NONMETALS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC BORON COMPOUNDS
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
POLYENES
RADIOISOTOPES
SPECTRA
STRUCTURAL CHEMICAL ANALYSIS
TRANSURANIUM COMPLEXES
YEARS LIVING RADIOISOTOPES