New paper accepted in Phys. Rev. Mater. exposes the limits of popular DFT functional
The manuscript reports on the near incident x-ray standing wave (NIXSW) quantitative structural determination of Co intercalation of graphene on Ir(111) and its theoretical description through density functional theory (DFT). Our collaborative work with Woodruff in Warwick Physics, the I09 team at the Diamond synchrotron, the Betti group in Rome, and the Blügel group in Jülich, shows how this specific system exposes the limits of a widely used ab initio van der Waals DFT functional.
Three manuscripts just accepted for publication
Three manuscripts have been accepted for publication in the last week. All three papers report about collaborative work with experimental and theoretical groups around the world.
In the first paper we applied our ESD-STM technique to the analysis of a new type of conjugated polymer (TBIDT-BT) made by the McCulloch group at KAUST, whose physical properties were measured by the Sirringhaus group in Cambridge. Our contribution allowed to determine that the slightly reduced device performance of TBIDT-BT, when compared with the related superstar polymer IDT-BT, is most probably due to the formation of nanovoids in the polymer assembly. The paper is due to appear in the Journal of the American Chemical Society.
The second paper is a new chapter in the long-standing collaboration with Professor Woodruff in Physics at Warwick and investigates the structural phases formed by 7,7,8,8-tetracyanoquinodimethane (TCNQ) on the Ag(111) surface. Besides reporting a combination of STM and near incident x-ray standing wave (NIXSW) measurements, in this paper we applied also low energy electron microscopy (LEEM) to the study of this system, by cooperating with the group of Christian Kumpf at the Forschungszentrum Juelich. The paper will appear in Physical Review Materials.
The last paper originates from the work conducted by Professor Takayuki Suzuki from Fukuoka University during his sabbatical year in Warwick and investigate the interaction of TCNQ with the Si(111)-√7×√3-In surface superconductor. We demonstrate that TCNQ forms 2D metal organic network with In atoms form the substrate and that this is accompanied by a structural phase transition from the √7×√3 to a previously unknown 5 × 5 reconstruction. In order to rationalise the experimental finding, we partnered with the group of Peter Kratzer from the University of Duisburg-Essen whose DFT calculations indicate that the phase transition is driven by the surface reduction of In coverage. The paper will appear in Nanoscale.
James wins prize for best talk at Postgraduate Symposium
Congratulations to James for winning the prize for the best Physical, Theoretical, and Computational Chemistry talk at the annual Postgraduate Symposium of the Chemistry Department.
James picks up the baton from Dan, who won the same prize last year. Two prizes in two years: the bar is set quite high and the challenge is on for next year!
Paper accepted in ChemPhysChem on the physisorption of TCNQ on the Bi2Se3 topological insulator
In this work, we have studied the absorption of a prototypical molecular electron acceptor, TCNQ, on the (0001) surface of the Bi2Se3 topological insulator. Scanning tunneling microscopy, photoemission spectroscopy and density functional theory calculations reveal a negligible charge transfer and an essentially unperturbed electronic structure of the substrate, outlining an overall physisorption picture. The results reveal a significant potential of TCNQ for the realization of metal-organic coordination networks on topological insulator surfaces.
The paper is the result of a multinational collaboration with the Università della Calabria (Italy), Saint Petersburg State University and Tomsk State University (Russia), Azerbaijan State Oil and Industry University (Azerbaijan), and the Donostia International Physics Center in San Sebastián (Spain).
James wins prize for best talk
James Edmondson won the prize for the best presentation at the 2018 MAS-CDT Annual Conference, that took place last week in Derbyshire.
Welcome to Marco Turano
Marco Turano joins us today as a new PhD student. Marco is Italian and graduated with a Masters in Physics from the Università della Calabria (Italy) in September 2017.
Marco’s project will be in collaboration with Lubrizol on developing a fundamental understanding of corrosion inhibitor adsorption within the MAS-CDT programme.
Don Eigler visits our labs
Don Eigler, the first man to move individual atoms with a STM almost exactly 25 years ago, received the title of Honorary Doctor of Science by the University of Warwick during the morning graduation ceremony on Monday, July 17th (yes, the same where Alex was given his degree!).
Don gave an inspiring Public Lecture with the title “Atom Manipulation – The Story and the People” on Tuesday the 18th (11:30 am, Ramphal Lecture Theatre) and visited our labs in the afternoon.
It was an amazing experience for all the group to be able to present their work to such a distinguished scientist. The pinnacle was reached when Don deemed as “officially cool” our mini-hexapole ion guide, part of the electrospray ion beam deposition setup.
Congratulations to Alex for his Graduation
On Monday July 17th, an unusually hot day, Alex graduated with honours in Chemistry with an excellent final year result mainly based on his project on the thermal sublimation and cyclisation of dipeptides in our lab.
Paper accepted in PRB on the structure of the Si(111)-√7×√3-In surface
Prof Takayuki Suzuki, a long-term collaborator of our group who spent his 2015-16 sabbatical year in our laboratory, headed a collaboration between Fukuoka University in Japan, the University of Duisburg-Essen in Germany and our group at Warwick to precisely determine the structure of the Si(111)-√7×√3-In surface. This surface has recently been at the centre of several scientific publications due to its two-dimensional metallic state and its low-temperature superconductivity. Our just-accepted paper has very clearly determined the presence of two layers of In and, by comparison with first principle density functional theory calculations established the precise structure of the bilayer.
Dan wins prize for best talk at Postgraduate Symposium
Congratulations to Dan for winning the prize for the best Physical, Theoretical, and Computational Chemistry talk at the annual Postgraduate Symposium of the Chemistry Department.
Dan being congratulated by the Head of Department, Prof. Martin Wills