Complexes Containing a Direct, Unsupported Lanthanide-Transition Metal Bond

Burns, Corey P.

Complexes Containing a Direct, Unsupported Lanthanide-Transition Metal Bond

dc.contributor.advisor	Nippe, Michael
dc.contributor.committeeMember	Fang, Lei
dc.contributor.committeeMember	Grunlan, Jamie C
dc.contributor.committeeMember	Zhou, Hong-Cai
dc.creator	Burns, Corey P.
dc.date.accessioned	2019-11-25T21:52:59Z
dc.date.available	2021-08-01T07:34:08Z
dc.date.created	2019-08
dc.date.issued	2019-07-12
dc.date.submitted	August 2019
dc.date.updated	2019-11-25T21:52:59Z
dc.description.abstract	The synthesis and characterization of molecules containing a direct, unsupported lanthanide transition metal bond is an ambitious task. Adding to this challenge, it is difficult to design a system in which both the lanthanide and transition metal can be interchanged to assess the nature of this interaction. As metal-metal bonding has provided significant insights into chemical bonding, catalysis, and electronic structure, it is important to pursue this rarely reported interaction. Additionally, lanthanide-transition metal heterometallics have drawn recent interest in the field of single-molecule magnetism (SMMs). Initially, dinuclear lanthanide complexes containing bridging chloride (Cl¯) or triflate (OCF3SO2 - ) ligands were isolated as synthons for future reactions. These complexes were successfully prepared by reacting a dysprosium salt with the previously reported 2,6- bis(methylenecyclopentadienyl)pyridine disodium salt Nav2PyCp2 (PyCpv2 = 2,6- (CHv2Cv5H3)2C5Hv3N]^2- ) to yield [(PyCpv2)Dy(μ-OTf)]v2 and [(PyCp2)Dy(μ-Cl)]2. Of note, this was the first structurally characterized organometallic dysprosium triflate complex. These complexes exhibited properties of an SMM as evidenced by static and dynamic magnetic measurements. Despite the identity of the bridging ligand differing in the compounds, both exhibited a similar energy barrier (U) to reorient spin. As dysprosium garners substantial attention in the field of SMMs, complexes containing a Dy-TM were first targeted. The reaction between [(PyCpv2)Dy(μ-OTf)]v2 and anionic transition metal fragments KFp or KRp (Fp = [CpFe(CO)v2] - , Rp = [CpRu(CO)v2]), afforded the complexes PyCpv2Dy-FeCp(CO)v2 and PyCp2Dy-RuCp(CO)v2. Infrared and Mössbauer spectroscopic studies suggested this interaction to be strong TM→Dy bonding interactions which is further supported by computational analysis. Magnetization dynamics performed in this study determined both compounds exhibited field induced slow magnetic relaxation with similar barriers despite different relaxation times. A later study compared the spectroscopic and magnetic properties of (thf)PyCpv2Ce-FeCp(CO)v2 to that of PyCpv2Dy-FeCp(CO)2 and concluded that the identity of the lanthanide has an influence on the magnetic properties of these heterobimetallic systems. Spectroscopic and computational analysis demonstrated weaker TM→Ln interactions in the (thf)PyCp2CeFeCp(CO)2 as compared to PyCp2Dy-FeCp(CO)v2. Preliminary findings on other Ln-TM bonded complexes isolated with this ligand system will be shared.	en
dc.format.mimetype	application/pdf
dc.identifier.uri	https://hdl.handle.net/1969.1/186516
dc.language.iso	en
dc.subject	Single-Molecule Magnetism	en
dc.subject	Lanthanide-Metal Bonding	en
dc.title	Complexes Containing a Direct, Unsupported Lanthanide-Transition Metal Bond	en
dc.type	Thesis	en
dc.type.material	text	en
local.embargo.terms	2021-08-01
local.etdauthor.orcid	0000-0001-8305-4239
thesis.degree.department	Chemistry	en
thesis.degree.discipline	Chemistry	en
thesis.degree.grantor	Texas A&M University	en
thesis.degree.level	Doctoral	en
thesis.degree.name	Doctor of Philosophy	en