Valence electron isomerism in the f-block

The valence electron configuration of a metal describes the relative ordering and properties of the highest-energy electrons - those that are available for bonding with other elements, and thus it is these which largely dictate the physicochemical properties of metal-containing materials.

For much of the Periodic Table, known principles guide the design criteria needed to produce a given electron configuration of the element in question to produce desired properties. The oxidation state of the metal - the (formal) number of electrons the metal has lost versus the neutral atomic configuration, and the stereochemistry of bound ligands are two of the most important features which can be controlled.

Lanthanide and actinide elements (the f-block) occupy a position in the periodic table where the valence electrons typically reside in highly angular 4f- and 5f-orbitals, which show poor radial extent, highly ionic bonding, and bound ligands generally only weakly affect the properties of these orbitals. It is these characteristics which engender unique physical properties typical of these metals (e.g. applications in magnetism and optical spectroscopy). The M(III) oxidation state dominates the chemistry of f-block metals, and trivalent ions typically have n (where n is an integer) valence f-electrons, where n is three less than in the neutral configuration, and there is little which may be done to change the chemical properties of the remaining f-electrons (though their physics may be altered).

In lower oxidation states, such as M(II), for some f-elements the valence electron configuration follows the pattern above and the metal contains f n+1 valence electrons where n is three less than the neutral atomic configuration – Sm(II) 4f6, Eu(II) 4f7, and Yb(II) 4f14 are examples of this. For other elements (such as Ce), all examples of M(II) complexes feature an electron configuration described as: f n d1, where n is still three less than the neutral atomic configuration, and one electron resides in a d-orbital (for Ce(II): f1 d1). As d-orbitals are fundamentally different to f-orbitals (larger radial extent, more diffuse, different magnetic properties), the physicochemical properties of M(II) molecules with valence d-electrons should differ substantially from molecules with f n electron configurations. Some elements, such as U, have been shown to accommodate both types of electron configuration in the M(II) oxidation state: f n+1, and also f n d1. The underlying properties which drive the preference for one configuration over the other are poorly known, are an under-explored topic at the forefront of synthetic chemistry, and is the focus of this fully funded PhD project.

The successful applicant will synthesise f-block coordination and organometallic compounds in formal low oxidation states using air-free (Schlenk line and glovebox) techniques, and structurally characterise them using single-crystal X-ray crystallography. Together with collaborators in ab initio quantum chemistry and EPR spectroscopy techniques, they will determine the effect of ligand donor properties and stereochemistry on metal valence electron configuration.The researcher will be trained in synthetic air-free inorganic/organometallic techniques, and characterisation methods such as single-crystal X-ray crystallography, NMR spectroscopy, SQUID magnetometry, EPR spectroscopy, and electrochemistry. Training in the handling and chemistry of actinides such as Th, and U will also be provided.

Please find guidance on the application process at: https://www.chemistry.manchester.ac.uk/study/postgraduate-research/how-to-apply/. Contact Dr Conrad Goodwin ([Email Address Removed], including a CV) for informal discussions before application, if desired.

The proposed start date is September 2024.

Eligibility

Applicants are expected to hold, or about to obtain, a minimum upper second-class (2:1) undergraduate degree (or the overseas equivalent) in Chemistry.

A Master’s degree in a relevant subject and experience in synthetic inorganic chemistry is desirable. Candidates with an interest in inorganic/organometallic air-free synthesis with lanthanide and actinide elements and/or experience in air/moisture-free chemistry are encouraged to apply.

Funding

At The University of Manchester, we offer a range of scholarships, studentships and awards at university, faculty and department level, to support both UK and overseas postgraduate researchers.

For more information, visit our funding page or search our funding database for specific scholarships, studentships and awards you may be eligible for.

Before you apply

We strongly recommend that you contact the supervisor(s) for this project before you apply.

How to apply

Apply online through our website: https://uom.link/pgr-apply-fap

When applying, you’ll need to specify the full name of this project, the name of your supervisor, if you already having funding or if you wish to be considered for available funding through the university, details of your previous study, and names and contact details of two referees.

Your application will not be processed without all of the required documents submitted at the time of application, and we cannot accept responsibility for late or missed deadlines. Incomplete applications will not be considered.

After you have applied you will be asked to upload the following supporting documents:

• Final Transcript and certificates of all awarded university level qualifications
• Interim Transcript of any university level qualifications in progress
• CV
• Contact details for two referees (please make sure that the contact email you provide is an official university/work email address as we may need to verify the reference)
• English Language certificate (if applicable)

If you have any questions about making an application, please contact our admissions team by emailing [Email Address Removed].

Equality, diversity and inclusion is fundamental to the success of The University of Manchester, and is at the heart of all of our activities. We know that diversity strengthens our research community, leading to enhanced research creativity, productivity and quality, and societal and economic impact.

We actively encourage applicants from diverse career paths and backgrounds and from all sections of the community, regardless of age, disability, ethnicity, gender, gender expression, sexual orientation and transgender status.

We also support applications from those returning from a career break or other roles. We consider offering flexible study arrangements (including part-time: 50%, 60% or 80%, depending on the project/funder).