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Abstract Coordination complexes of general formulatrans‐[MX2(R2ECH2CH2ER2)2] (MII=Ti, V, Cr, Mn; E=N or P; R=alkyl or aryl) are a cornerstone of coordination and organometallic chemistry. We investigate the electronic properties of two such complexes,trans‐[VCl2(tmeda)2] andtrans‐[VCl2(dmpe)2], which thus representtrans‐[MX2(R2ECH2CH2ER2)2] where M=V, X=Cl, R=Me and E=N (tmeda) and P (dmpe). These VIIcomplexes haveS=3/2 ground states, as expected for octahedral d3. Their tetragonal distortion leads to zero‐field splitting (zfs) that is modest in magnitude (D≈0.3 cm−1) relative to analogousS=1 TiIIand CrIIcomplexes. This parameter was determined from conventional EPR spectroscopy, but more effectively from high‐frequency and ‐field EPR (HFEPR) that determined the sign ofDas negative for the diamine complex, but positive for the diphosphine, which information had not been known for anytrans‐[VX2(R2ECH2CH2ER2)2] systems. The ligand‐field parameters oftrans‐[VCl2(tmeda)2] andtrans‐[VCl2(dmpe)2] are obtained using both classical theory andab initioquantum chemical theory. The results shed light not only on the electronic structure of VIIin this environment, but also on differences between N and P donor ligands, a key comparison in coordination chemistry.
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This content will become publicly available on February 25, 2027
Astrochemistry prefers the biomolecule: isomer-selective production of ethanolamine (HOCH 2 CH 2 NH 2 ) in interstellar model ices
Model interstellar ices composed of methanol and methylamine are found to efficiently and selectively produce ethanolamine (HOCH2CH2NH2) without side reactions leading to its isomers. Credit: NASA/ESA/CSA.
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- Award ID(s):
- 2403867
- PAR ID:
- 10678493
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- Volume:
- 28
- Issue:
- 8
- ISSN:
- 1463-9076
- Page Range / eLocation ID:
- 5516 to 5526
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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