Advanced structural characterization of metal-organic frameworks by quantum-crystallographic methods and electron diffraction

The aim of the project is advanced structural characterization of metal-organic framework (MOF) materials by means of X-ray and electron diffraction methods, coupled with quantum-crystallographic methods for accurate determination of atom positions and assignment of guest molecule arrangements within MOF voids.

 Structural characterization of MOFs by X-ray diffraction is a challenging task due to comparatively poor quality of the corresponding crystals, and often disordered nature of guest molecules within the pores of their structures. The lack of atomic precision in locating the guest species may result in their incorrect assignment, and generally makes it difficult to understand host-guest interactions present in such structures.

 We have recently demonstrated how the accuracy of MOF structural characterization can be greatly improved thanks to the use of Hirshfeld Atom Refinement (HAR) method for processing of standard resolution X-ray diffraction data. Thanks to the HAR method, positions of hydrogen atoms within the structure could be accurately determined, and their anisotropic thermal motion fully characterized. Moreover, higher sensitivity of HAR enabled identification of previously unreported guest molecule disorder.

 The successful candidate will be engaged in advanced structural characterization of MOF materials through the use of X-ray and electron diffraction, followed by quantum-mechanical treatment of the diffraction data for the purpose of obtaining the most accurate structural models. The use of electron diffraction opens another exciting opportunity, where the tiniest crystallites of less than 100 nm in size can be used to collect diffraction data suitable for structure determination. We will use electron diffraction to structurally-characterize MOFs synthesized by mechanochemical methods, which offer a rapid, high-yield and energy-efficient path to a wide range of MOF structures which are often difficult to obtain by solution-based methods.

 The successful candidate will become part of the project team dedicated to the design of new hypergolic MOFs, exploring computational approaches for structure and property prediction of these materials, along with experimental synthesis and characterization.

 The PhD student will be exposed to cutting-edge structural characterization methods developed at the Crystallochemistry Laboratory at the Faculty of Chemistry, University of Warsaw. Moreover, the candidate will have the opportunity to gain experience in mechanochemical MOF synthesis during the planned three-month research visit to the group of Prof. Tomislav Friščić at the School of Chemistry, University of Birmingham.

 To enquire about the project please email [email protected]. For further information about the Arhangelskis group please visit the group website www.arhangelskis.org

Necessary qualifications: 

·      MSc degree in chemistry, materials science or related fields.

·      Experience with single-crystal X-ray diffraction data collection, crystal structure solution and refinement.

·      Good command of spoken and written English.

Additional skills which would be advantageous:

·      Experience with solid-state characterization techniques (e. g. powder X-ray diffraction, thermal methods, solid-state NMR).

·      Experience with electron diffraction.

·      Experience with quantum crystallography.

We offer a temporary 48 month contract with the University of Warsaw. The successful candidate will receive a stipend of 5000 PLN/month for the first 24 month of the project, which will be increased to 5340,90 PLN/month after mid-term evaluation.

 There is also a possibility to receive additional stipend from the University of Warsaw Doctoral School of Exact and Natural Sciences. The nearest possibility to apply for this stipend will be June 2025, i. e. for the 2^nd-4^th years of the Doctoral studies. The PI will support the PhD candidate in preparing the application for this additional stipend. The amount of this additional stipend is 4242 PLN/month during until the end of 2^nd year of PhD studies, increasing to 5340.90 PLN/month in years 3 and 4.

Necessary documents:

Cover letter highlighting previous research experience and explaining the suitability of the candidate for the advertised position.

CV

Scan of the Masters’ degree certificate (if already available)

Contact details of two referees.

Signed consent for the processing of personal data by the University of Warsaw.

Please email all the documents no later than 30/08/2024 to [email protected] with a subject “PhD application HAR”. Applications submitted after the deadline will not be considered. Selected candidates will be informed about the date of the interview by e-mail no later than 10/09/2024. Interviews will be conducted remotely. Following the interview, the selected candidate will be appointed to the Doctoral School of Exact and Natural Sciences of the University of Warsaw.