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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 May 27, 2026
Raman spectroscopy of 2D MoS 2 on Ti 3 C 2 MXene: the substrate effect
Red-shifted and broadened Raman peaks of MoS2reveal the strain and doping effects from Ti3C2MXene as a substrate.
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- Award ID(s):
- 2048164
- PAR ID:
- 10598102
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Nanoscale Advances
- Volume:
- 7
- Issue:
- 11
- ISSN:
- 2516-0230
- Page Range / eLocation ID:
- 3456 to 3461
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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