Dr Paul J. Low

(email at p.j.low@durham.ac.uk)

Research Interests

Our research goals are centred around the synthesis and characterisation molecular materials, coupled with identification of structure-property relationships in these systems. The work carried out in our group crosses the boundaries of fundamental and applied science, and as a consequence is supported by grants from the EPSRC, the Royal Society, the local regional economic development agency ONE North East, as well through interactions with national (Avecia Ltd) and international (SONY) industrial interests. We are formally based with the Inorganic, Structural and Materials research grouping, but our systems of interest span a range of core structures from organometallic mononuclear species and clusters to entirely organic materials.

We work in a dedicated, well-equipped synthetic laboratory which houses six fumehoods fitted with the usual array of Schlenk-type vacuum lines and glassware, and a double-length Innovative Technologies inert atmosphere glovebox. Our en-suite instrument room contains the groups Avatar IR spectrometer, the Cary 5 UV-Vis-NIR spectrophotometer, and a state-of-the-art EcoChemie Autolab PGSTAT-30 potentiostat. Spectroelectrochemical cells for both the Avatar and the Cary allow us to perform continuous coverage (500-50,000 cm^-1) spectroelectrochemical studies on our systems.

In addition to the synthetic and electrochemical/spectroelectrochemical work carried out within the research laboratory, we collaborate with groups based in the Department [e.g. Prof J.A.K. Howard (X-ray diffraction-based structure determination), Dr Andy Beeby (photochemistry and photophysics), Prof. T.B. Marder (synthesis)], within the UK [e.g. Dr LesleyYellowlees (University of Edinburgh, ESR spectroscopy), Dr P. Christensen (University of Newcastle, IR spectroelectrochemistry)] and around the world [e.g. Dr J-F. Halet, (CNRS/Universite Rennes 1, computational chemistry), Prof. M.I. Bruce (University of Adelaide, synthesis), Dr F. Hartl (University of Amsterdam, spectroelectrochemistry), Dr C. Nervi (University of Turin, electrochemistry)].

Organometallic Chemistry^1,2

Over the last 10 years we, and others, have shown that chains comprised solely of carbon, C_n, can be stabilised by coordination to two or more metal centres. Studies of simple linear systems [{L_xM}-C_n-{ML_x}]^y+ have shown remarkably facile intra-molecular electron transfer (or delocalisation) can occur between the metal centres via the carbon chain, sparking great interest in these systems as molecular wires. We are pursuing this work both from the point of view of engineering useful electronic properties, as well as mapping the chemical reactivity of this C_n building block. Other work is concerned with the use of the carbon chain as a scaffold for the assembly of metal clusters, and in the chemistry of derivatives including diethynyl aromatic systems, and the fascinating cyanoacetylide ligand, C≡CC≡N.

Hole-Transport Materials^3,4

There is an intense interest in N,N,N’,N’-tetraaryl-(1,1’-biphenyl)-4,4’diamine based structures as hole injecting and transporting materials for use in a wide range of present and future applications. We are concerned with establishing relationships between the molecular structure of these compounds and physical characteristics such as oxidation (or ionisation) potential, molecular arrangement in the solid state, reorganisation energy upon charge transfer and environmental stability, as each of these properties will influence the hole transport performance of the compound in a device.

Linear and Cross-Conjugated Organic Materials^5,6

Conjugated organic materials continue to fascinate by displaying a range of electronic (e.g. wire-like delocalisation of electrons), photophysical (e.g. luminescence/electroluminescence) and physical (e.g. liquid-crystalline) behaviour. We are interested not only in the development of simple syntheses of unusual conjugated systems, but also in the tailored design of materials for specific applications in the electronics and displays markets.

From left to right: A cyanoacetylide complex;² the first crystallographically characterised example of the radical cation derived from a hole-transport material;³ two ring conformations of 1,4-bis(phenylethynyl)benzene.⁵

References

1. MI Bruce and PJ.Low Adv. Organomet. Chem., 2004, 50, 179.
2. RL Cordiner, D. Corcoran, DS Yufit, AE Goeta, J.A.K Howard, and PJ Low, Dalton Trans., 2003, 3541.
3. PJ Low, MAJ Paterson, H Puschmann, AE Goeta, JAK Howard, C Lambert, JC Cherryman, DR Tackley, S Leeming, B Brown, Chem. Eur. J. 2004, 10, 83.
4. RE Littleford, MAJ Paterson, PJ Low, DR Tackley, L Jayes, G Dent, JC Cherryman, WE Smith, Phys. Chem., Chem. Phys., 2004, <6, 3257.
5. A Beeby, K Findlay, PJ Low, TB Marder, P Matousek, AW Parker, SR Rutter, M Towrie, Chem. Commun., 2003, 2406.
6. OF Koentjoro, P Zuber, H Puschmann, AE Goeta, JAK Howard, PJ Low, PJ, J. Organomet. Chem., 2003, 670, 178.