Staff profile

Prof J. A. Gareth Williams studied for an M.A. in Chemistry at Merton College, University of Oxford, including a Part 2 research project on the chemistry of dinuclear tungsten complexes in the group of Prof. Malcolm L. H. Green FRS. He then moved to the University of Durham to study for a PhD with Prof. David Parker on the luminescence properties of macrocyclic metal complexes. This was followed by a postdoctoral fellowship at Universite Louis Pasteur, Strasbourg, with Prof. Jeane-Pierre Sauvage (Nobel laureate 2016), working on the synthesis of multiporphyin assemblies, and the study of energy- and electron transfer processes within them, in collabroation with researchers at the C.N.R. Bologna, Italy.

Following further EPSRC-funded postdoctoral research on stereoselctive energy transfer, Williams was appointed to a lectureship at Durham University, and duly promoted to Senior Lecturer and then Professor in 2012.

Research Interests

Prof. J. A. Gareth Williams' research interests are centred around the synthesis and properties of light-emitting molecules. Applications include: (i) organic light-emitting diodes (OLEDs) for new flat-screen display technology, (ii) luminescent probes for bioimaging and as sensors for bioactive molecules in solution, and (iii) photosensitisers of energy- and electron-transfer for solar energy conversion.

We are also interested in the bacteristatic effects of ligands related to EDTA - how such chelants can interfere with the ability of bacteria to acquire the metal ions they need to survive. Such research has huge implications for the shelf-life of many consumer products, ranging from mayonnaise to face cream! 

Our synthetic work includes both organic synthesis and the coordination chemistry of transition metal and lanthanide ions. We also study the luminescence and photophysical properties of conjugated organic molecules and new metal complexes. The work is multi-disciplinary in nature and embraces all three of the main branches of chemistry. We have close links with Universities in France, Italy and North America, and industrial laboratories in the UK and USA.

Cyclometallated platinum(II) and iridium(III) complexes

Organic light emitting devices (OLEDs) are set to be at the forefront of future display screen technology. Luminescent, charge-neutral complexes of third-row transition metal ions will be important as "triplet-harvesting agents" in OLEDs. The high spin-orbit coupling constant of these heavy metal ions promotes emission from the triplet excited states that are normally non-emissive and wasted in such devices, allowing huge gains in efficiency and lower power consumption. Charge-neutral complexes can be obtained by cyclometallation: formation of a metal-carbon bond within a chelate ring. We are investigating N^C^N-coordinating ligands for this purpose, bound to Pt(II) and Ir(III).^{1, 2}

For example, the platinum complexes of these ligands are amongst the most emissive ever reported, with quantum yields in excess of 60%, and the colour of emission can be tuned from green to red according to the substituents on the ligand.² These compounds function well in OLEDs giving very efficient performance.³ At high concentrations, intense excimer emission is also observed and, by choosing an appropriate concentration, the combination of blue-green emission from isolated molecules with red excimer emission leads to the production of white light, a feature that is attractive for lighting applications. The figure shows four OLEDs prepared using different concentrations of platinum and the different colours that result, superimposed on the CIE coordinates. The asterisk indicates the ideal position for ambient room lighting – we’re not far off! ⁴

We’re also exploring the utility of these compounds as oxygen sensors. By immobilising them in an ethyl cellulose film also containing platinum octaethylporphyrin, a wide-range O₂ sensor is obtained that responds as a molecular traffic light.²

Molecular LEGO: Cross-couplings in the synthesis of photoactive multimetallic assemblies

We have pioneered the use of palladium-catalysed cross-coupling reactions for building on the back of metal-bound ligands. For example, ruthenium(II) and iridium(III) complexes with bipyridyl and terpyridyl ligands, incorporating a bromo substituent, can react with aryl boronic acids, offering a reliable route to larger systems. We have also shown that boronic acid functionality can be introduced into such metal complexes. But most significant is the fact that these two mutually complementary types of complex can be cross-coupled with one another, leading to a controlled synthesis of multimetallic assemblies. An example is shown in the figure. This "building block" approach offers major advantages of control and diversity over conventional methods which rely on pre-formed bridging ligands. Photosensitised energy and electron transfer processes between the metal centres are being investigated using time-resolved spectroscopy. See our recently published book chapter on Multinuclear Iridium Complexes for more details of this area of our research.⁵

Luminescent sensors for bioactive ions and molecules in solution

Although a large number of fluorescent sensors for a variety of species are commercially available, most rely on changes in the wavelength or intensity of the short-lived (nanosecond) emission. We are seeking to develop new light-emitting components for sensors, in which the emission is long-lived, in the microsecond-to-millisecond range. This allows time-resolved detection methods of analysis to be employed, which gets round the problem of background interference from other fluorescent material, and also offers the potential for lifetime-based sensing. See our recent book chapter for more about the background to time-resolved imaging.⁶

We are investigating a number of systems for this purpose, including cyclometallated platinum(II) and iridium(III) complexes, together with their interactions with a variety of biologically active ions and molecules. The group is studying the use of such brightly emissive metal complexes as novel imaging agents in live cells.^7,8 The figure shows a culture of CHO cells under a fluorescent microscope, which have been incubated with a new iridium complex that accumulates and emits brightly in the nucleoli. Some of the iridium complexes under study also show potential for photodynamic therapy - for the light-activated destruction of cancer cells.⁹ 

References

1. L. F. Gildea and J. A. G. Williams, Iridium and platinum complexes for OLEDs, in "Organic light-emitting diodes: Materials, devices and applications", ed. A. Buckley, Woodhead, 2013.
   
2. J. A. G. Williams, Chem. Soc. Rev., 2009, 38, 1783-1801.
3. J. Kalinowski, V. Fattori, M. Cocchi and J. A. G. Williams, Coord. Chem. Rev., 2011, 255, 2401-2425.
4. L. Murphy, P. Brulatti, V. Fattori, M. Cocchi and J. A. G. Williams, Chem. Commun., 2012, 48, 5817-5819.
5. J. A. G. Williams, Multinuclear Iridium Complexes in "Iridium(III) In Optoelectronics and Photonics Applications" ed. E. Z. Colman, Wiley, 2017. 
6. E. Baggaley, J. A. Weinstein and J. A. G. Williams, "Time-resolved emission imaging microscopy using phosphorescent metal complexes: taking FLIM and PLIM to new lengths", Struct. Bond., 2015, 165, 205-256.
7. E. Baggaley, S. W. Botchway, J. W. Haycock, H. Morris, I. V. Sazanovich, J. A. G. Williams and J. A. Weinstein, Chem. Sci., 2014, 5, 879-886.
8. E. Baggaley, I. V. Sazanovich, J. A. G. Williams, J. W. Haycock, S. W. Botchway and J. A. Weinstein, RSC Advances, 2014, 4, 35003-35008.
9. L. K. McKenzie, I. V. Sazanovich, E. Baggaley, M. Bonneau, V. Guerchais, J. A. G. Williams, J. A. Weinstein and H. E. Bryant, Chem. Eur. J., 2017, 23, 234-238.

• Synthetic Chemistry
• Metal Complexes
• Luminescence and Bioimaging

Journal Article

• Pander, P., Walden, M. T., Salthouse, R. J., Sil, A., Yufit, D. S., Dias, F. B., & Williams, J. A. G. (2023). Rigidly linked dinuclear platinum( ii ) complexes showing intense, excimer-like, near-infrared luminescence. Journal of Materials Chemistry C Materials for optical and electronic devices, 11(43), 15335-15346. https://doi.org/10.1039/d3tc03432a
• Montagu, J., Gontard, G., Williams, J. A. G., & Moussa, J. (2023). Cyclometallated Platinum(II) Complexes Featuring an Unusual, C^N‐Coordinating Pyridyl‐pyridylidene Ligand and L X Coligands: Synthesis, Structures and Dual Luminescence Behavior. European Journal of Inorganic Chemistry, 26(32), Article e202300487. https://doi.org/10.1002/ejic.202300487
• Salthouse, R. J., Sil, A., Gildea, L. F., Yufit, D. S., & Williams, J. A. G. (2023). Platinum(II) Complexes of Nonsymmetrical NCN-Coordinating Ligands: Unimolecular and Excimeric Luminescence Properties and Comparison with Symmetrical Analogues. Inorganic Chemistry, 62(31), 12356-12371. https://doi.org/10.1021/acs.inorgchem.3c01439
• Dikova, Y. M., Yufit, D. S., & Williams, J. G. (2023). Platinum(IV) Complexes with Tridentate, NNC-Coordinating Ligands: Synthesis, Structures, and Luminescence. Inorganic Chemistry, 62(4), 1306-1322. https://doi.org/10.1021/acs.inorgchem.2c04116
• Kundu, D., del Rio, N., Cordier, M., Vanthuyne, N., Puttock, E. V., Meskers, S. C. J., …Crassous, J. (2023). Enantiopure cycloplatinated pentahelicenic N-heterocyclic carbenic complexes that display long-lived circularly polarized phosphorescence. Dalton Transactions, 52(19), 6484-6493. https://doi.org/10.1039/d3dt00577a
• Gauthier, E. S., Abella, L., Caytan, E., Roisnel, T., Vanthuyne, N., Favereau, L., …Crassous, J. (2023). Modulation of chiroptical and photophysical properties in helicenic rhenium(I) systems: the use of an N‐(aza[6]helicenyl)‐NHC ligand. Chemistry - A European Journal, 29(21), Article 202203477. https://doi.org/10.1002/chem.202203477
• Lozada, I. B., Braun, J. D., Williams, J. G., & Herbert, D. E. (2022). Yellow-Emitting, Pseudo-Octahedral Zinc Complexes of Benzannulated N^N^O Pincer-Type Ligands. Inorganic Chemistry, 61(44), 17568-17578. https://doi.org/10.1021/acs.inorgchem.2c02585
• Crassous, J., Gauthier, E. S., Kaczmarczyk, D., Fré, S. D., Favereau, L., Caytan, E., …Srebro-Hooper, M. (2022). Helicenic N-heterocyclic carbene copper(I) complex displaying circularly polarized blue fluorescence. Dalton Transactions, 51(40), 15571-15578. https://doi.org/10.1039/d2dt01925f
• Pander, P., Sil, A., Salthouse, R. J., Harris, C. W., Walden, M. T., Yufit, D. S., …Dias, F. B. (2022). Excimer or aggregate? Near infrared electro- and photoluminescence from multimolecular excited states of N^C^N-coordinated platinum(ii) complexes. Journal of Materials Chemistry C Materials for optical and electronic devices, 10(40), 15084-15095. https://doi.org/10.1039/d2tc01511k
• Nemez, D. B., Lozada, I. B., Braun, J. D., Williams, J. G., & Herbert, D. E. (2022). Synthesis and Coordination Chemistry of a Benzannulated Bipyridine: 6,6′-Biphenanthridine. Inorganic Chemistry, 61(34), 13386-13398. https://doi.org/10.1021/acs.inorgchem.2c01514
• Mullins, A. L., Ćirić, A., Zekovic, I., Williams, J. G., Dramicanin, M., & Evans, I. R. (2022). Dual-emission luminescence thermometry using LaGaO3:Cr3+, Nd3+ phosphors. Journal of Materials Chemistry C Materials for optical and electronic devices, 10(28), 10396-10403. https://doi.org/10.1039/d2tc02011d
• Parker, R. R., Stracey, R. F., McEllin, A. J., Chen, X., Wang, Y., Williams, J. G., …Bruce, D. W. (2022). Synthesis, Mesomorphism, Photophysics, and Device Properties of Liquid-Crystalline Pincer Complexes of Gold(III) Containing Semiperfluorinated Chains. ACS Omega, 7(28), 24903-24917. https://doi.org/10.1021/acsomega.2c03669
• Mullins, A. L., Ćirić, A., Ristić, Z., Williams, J. G., Radosavljević Evans, I., & Dramićanin, M. D. (2022). Double-deconvolution method for the separation of thermalised emissions from chromium-doped lanthanum gallate and its potential in luminescence-based thermometry. Journal of Luminescence, 246, https://doi.org/10.1016/j.jlumin.2022.118847
• Walden, M. T., Yufit, D. S., & Williams, J. G. (2022). Luminescent bis-tridentate iridium(III) complexes: Overcoming the undesirable reactivity of trans-disposed metallated rings using –N^N^N–coordinating bis(1,2,4-triazolyl)pyridine ligands. Inorganica Chimica Acta, 532, Article 120737. https://doi.org/10.1016/j.ica.2021.120737
• Lozada, I. B., Williams, J. G., & Herbert, D. E. (2022). Platinum(ii) complexes of benzannulated N∧N−∧O-amido ligands: bright orange phosphors with long-lived excited states. Inorganic Chemistry Frontiers, 9(1), 10-22. https://doi.org/10.1039/d1qi01120k
• Lozada, I. B., Ortiz, R. J., Braun, J. D., Williams, J. G., & Herbert, D. E. (2022). Donor-Acceptor Boron-Ketoiminate Complexes with Pendent N-Heterocyclic Arms: Switched-on Luminescence through N-Heterocycle Methylation. Journal of Organic Chemistry, 87(1), 184-196. https://doi.org/10.1021/acs.joc.1c02138
• Salthouse, R. J., Pander, P., Yufit, D. S., Dias, F. B., & Williams, J. G. (2022). Near-infrared electroluminescence beyond 940 nm in Pt(N^C^N)X complexes: influencing aggregation with the ancillary ligand X. Chemical Science, 13(45), 13600-13610. https://doi.org/10.1039/d2sc05023d
• Paterson, J. R., Beecroft, M. S., Mulla, R. S., Osman, D., Reeder, N. L., Caserta, J. A., …Sharples, G. J. (2022). Insights into the antibacterial mechanism of action of chelating agents by selective deprivation of iron, manganese and zinc. Applied and Environmental Microbiology, https://doi.org/10.1128/aem.01641-21
• Wood, E. A., Gildea, L. F., Yufit, D. S., & Williams, J. G. (2021). Synthesis, structures and luminescence properties of N^C^N-coordinated platinum(II) complexes based on an anthracene core: a red shift and a twist. Polyhedron, 207, Article 115401. https://doi.org/10.1016/j.poly.2021.115401
• Gauthier, E. S., Cordier, M., Dorcet, V., Vanthuyne, N., Favereau, L., Williams, J. G., & Crassous, J. (2021). Helically chiral NHC‐gold(I) complexes: synthesis, chiroptical properties and electronic features of the [5]helicene‐imidazolylidene ligand. European Journal of Organic Chemistry, 2021(34), 4769-4776. https://doi.org/10.1002/ejoc.202100722
• Pander, P. H., Zaytsev, A., Sil, A., Williams, J. G., Lanoë, P., Kozhevnikov, V. N., & Dias, F. B. (2021). The Role of Dinuclearity in Promoting Thermally Activated Delayed Fluorescence (TADF) in Cyclometallated, N^C^N-coordinated Platinum(II) Complexes. Journal of Materials Chemistry C Materials for optical and electronic devices, 9(32), 10276-10287. https://doi.org/10.1039/d1tc02562g
• Crassous, J., Gauthier, E. S., Hellou, N., Caytan, E., Fré, S. D., Vanthuyne, N., …Srebro-Hooper, M. (2021). Triskelion-shaped iridium-helicene NHC complex. Inorganic Chemistry Frontiers, 8(16), 3916-3925. https://doi.org/10.1039/d1qi00527h
• Rodriguez-Garcia, M. M., Ćirić, A., Ristić, Z., Williams, J. G., Dramicanin, M., & Evans, I. R. (2021). Narrow-band red phosphors of high colour purity based on Eu3+-activated apatite-type Gd9.33(SiO4)6O2. Journal of Materials Chemistry C Materials for optical and electronic devices, 9(23), 7474-7484. https://doi.org/10.1039/d1tc01330k
• Walter, E. R., Hogg, C., Parker, D., & Gareth Williams, J. (2021). Designing magnesium-selective ligands using coordination chemistry principles. Coordination Chemistry Reviews, 428, Article 213622. https://doi.org/10.1016/j.ccr.2020.213622
• Puttock, E. V., Sturala, J., Kistemaker, J. C., & Williams, J. G. (2021). Platinum(II) Complexes of Tridentate ‐Coordinating Ligands Based on Imides, Amides, and Hydrazides: Synthesis and Luminescence Properties. European Journal of Inorganic Chemistry, 2021(4), 335-347. https://doi.org/10.1002/ejic.202000879
• Ortiz, R. J., Braun, J. D., Williams, J. G., & Herbert, D. E. (2021). Brightly Luminescent Platinum Complexes of N∧C–∧N Ligands Forming Six-Membered Chelate Rings: Offsetting Deleterious Ring Size Effects Using Site-Selective Benzannulation. Inorganic Chemistry, https://doi.org/10.1021/acs.inorgchem.1c02551
• Kos, M., Rodríguez, R., Storch, J., Sýkora, J., Caytan, E., Cordier, M., …Crassous, J. (2021). Enantioenriched Ruthenium-Tris-Bipyridine Complexes Bearing One Helical Bipyridine Ligand: Access to Fused Multihelicenic Systems and Chiroptical Redox Switches. Inorganic Chemistry, https://doi.org/10.1021/acs.inorgchem.1c01379
• Shafikov, M. Z., Pander, P., Zaytsev, A. V., Daniels, R., Martinscroft, R., Dias, F. B., …Kozhevnikov, V. N. (2021). Extended ligand conjugation and dinuclearity as a route to efficient platinum-based near-infrared (NIR) triplet emitters and solution-processed NIR-OLEDs. Journal of Materials Chemistry C Materials for optical and electronic devices, 9(1), 127-135. https://doi.org/10.1039/d0tc04881j
• Parker, R. R., Liu, D., Yu, X., Whitwood, A. C., Zhu, W., Williams, G., …Bruce, D. W. (2021). Synthesis, Mesomorphism, Photophysics and Device Performance of Liquid-crystalline Pincer Complexes of Gold(III). Journal of Materials Chemistry C Materials for optical and electronic devices, https://doi.org/10.1039/d0tc04839a
• Crassous, J., Saleh, N., Kundu, D., Vanthuyne, N., Olesiak, J., Pniakowska, A., …Autschbach, J. (2020). Synthesis, structure, photophysical and chiroptical properties of dinuclear rhenium complexes with a bridging helicene‐bis‐bipyridine ligand. ChemPlusChem, 85(11), 2446-2454. https://doi.org/10.1002/cplu.202000559
• Mandapati, P., Braun, J. D., Lozada, I. B., Williams, J. G., & Herbert, D. E. (2020). Deep-Red Luminescence from Platinum(II) Complexes of N^N–^N-Amido Ligands with Benzannulated N-Heterocyclic Donor Arms. Inorganic Chemistry, 59(17), 12504-12517. https://doi.org/10.1021/acs.inorgchem.0c01584
• Puttock, E. V., Sil, A., Yufit, D. S., & Williams, J. G. (2020). Mono and dinuclear iridium(iii) complexes featuring bis-tridentate coordination and Schiff-base bridging ligands: the beneficial effect of a second metal ion on luminescence. Dalton Transactions, 49(30), 10463-10476. https://doi.org/10.1039/d0dt01964j
• Crassous, J., Gauthier, E. S., Abella, L., Hellou, N., Darquié, B., Caytan, E., …Autschbach, J. (2020). Long‐lived circularly‐polarized phosphorescence in helicene‐NHC‐rhenium(I) complexes: the influence of helicene, halogen and stereochemistry on emission properties. Angewandte Chemie International Edition, 59(22), 8394-8400. https://doi.org/10.1002/anie.202002387
• Zhang, Z., Tizzard, G. J., Williams, J. G., & Goldup, S. (2020). Rotaxane Pt(II)-Complexes: Mechanical Bonding for Chemically Robust Luminophores and Stimuli Responsive Behaviour. Chemical Science, 7(11), 1839-1847. https://doi.org/10.1039/c9sc05507j
• Mandapati, P., Braun, J. D., Killeen, C., Davis, R. L., Williams, J. G., & Herbert, D. E. (2019). Luminescent Platinum(II) Complexes of N^N–^N Amido Ligands with Benzannulated N-Heterocyclic Donor Arms: Quinolines Offer Unexpectedly Deeper Red Phosphorescence than Phenanthridines. Inorganic Chemistry, 58(21), 14808-14817. https://doi.org/10.1021/acs.inorgchem.9b02480
• Puttock, E., Fradgley, J., Yufit, D., & Williams, J. (2019). A family of readily synthesised phosphorescent platinum(II) complexes based on tridentate N^N^O-coordinating Schiff-base ligands. Dalton Transactions, 48(40), 15012-15028. https://doi.org/10.1039/c9dt03156a
• Zhang, X., Abid, S., Shi, L., Williams, J. G., Fox, M. A., Miomandre, F., …Paul-Roth, C. O. (2019). Fluorenylporphyrins functionalized by electrochromic ruthenium units as redox-triggered fluorescence switches. Dalton Transactions, 48(31), 11897-11911. https://doi.org/10.1039/c9dt02087j
• Rodriguez-Garcia, M. M., Williams, J. G., & Evans, I. R. (2019). Single-Phase White-Emitting Phosphors Based on Apatite-Type Gadolinium Silicate, Gd9.33(SiO4)6O2 Doped with Dy3+, Eu3+ and Tb3+. Journal of Materials Chemistry C Materials for optical and electronic devices, 7(25), 7779-7787. https://doi.org/10.1039/c9tc02336d
• Walden, M. T., Pander, P., Yufit, D. S., Dias, F. B., & Williams, J. G. (2019). Homoleptic platinum(ii) complexes with pyridyltriazole ligands: excimer-forming phosphorescent emitters for solution-processed OLEDs. Journal of Materials Chemistry C Materials for optical and electronic devices, 7(22), 6592--6606. https://doi.org/10.1039/c9tc00768g
• Dragonetti, C., Colombo, A., Fontani, M., Roberto, D., Williams, G., Scotto di Perrotolo, R., …Polo, S. (2019). A highly luminescent tetrahydrocurcumin Ir(III) complex with remarkable photoactivated anticancer activity. Chemistry - A European Journal, 25(33), 7948-7952. https://doi.org/10.1002/chem.201901527
• Crassous, J., Macé, A., Hellou, N., Hammoud, J., Martin, C., Nasser, G., …Carboni, B. (2019). An enantiopure cyclometallated iridium complex displaying long-lived phosphorescence both in solution and in the solid state. Helvetica Chimica Acta, 102(4), https://doi.org/10.1002/hlca.201900044
• Mondal, R., Lozada, I. B., Davis, R. L., Williams, J. G., & Herbert, D. E. (2019). Exploiting synergy between ligand design and counterion interactions to boost room temperature phosphorescence from Cu(i) compounds. Journal of Materials Chemistry C Materials for optical and electronic devices, 7(13), 3772-3778. https://doi.org/10.1039/c9tc00040b
• Shafikov, M. Z., Daniels, R., Pander, P., Dias, F. B., Williams, J. G., & Kozhevnikov, V. N. (2019). Dinuclear Design of a Pt(II) Complex Affording Highly Efficient Red Emission: Photophysical Properties and Application in Solution-Processible OLEDs. ACS Applied Materials and Interfaces, 11(8), 8182-8193. https://doi.org/10.1021/acsami.8b18928
• Etchells, I. M., Pfrunder, M. C., Williams, J. G., & Moore, E. G. (2019). Quantification of energy transfer in bimetallic Pt(ii)–Ln(iii) complexes featuring an N^C^N-cyclometallating ligand. Dalton Transactions, 48(6), 2142-2149. https://doi.org/10.1039/c8dt04640a
• Parker, R. R., Sarju, J. P., Whitwood, A. C., Williams, J. G., Lynam, J. M., & Bruce, D. W. (2018). Synthesis, Mesomorphism, and Photophysics of 2,5-Bis(dodecyloxyphenyl)pyridine Complexes of Platinum(IV). Chemistry - A European Journal, 24(71), 19010-19023. https://doi.org/10.1002/chem.201804026
• Puttock, E. V., Walden, M. T., & Williams, J. G. (2018). The luminescence properties of multinuclear platinum complexes. Coordination Chemistry Reviews, 367, 127-162. https://doi.org/10.1016/j.ccr.2018.04.003
• Parker, D., Walter, E., & Williams, J. (2018). APTRA-based luminescent lanthanide complexes displaying enhanced selectivity for Mg2+. Chemistry - A European Journal, 24(30), 7724-7733. https://doi.org/10.1002/chem.201800745
• Mulla, R., Beecroft, M., Pal, R., Aguilar, J., Pitarch-Jarque, J., García‐España, E., …Williams, J. (2018). On the antibacterial activity of azacarboxylate ligands: lowered metal ion affinities for bis-amide derivatives of EDTA do not mean reduced activity. Chemistry - A European Journal, 24(28), 7137-7148. https://doi.org/10.1002/chem.201800026
• Mondal, R., Lozada, I. B., Davis, R. L., Williams, J. G., & Herbert, D. E. (2018). Site-Selective Benzannulation of N-Heterocycles in Bidentate Ligands Leads to Blue-Shifted Emission from [(P^N)Cu]2(μ-X)2 Dimers. Inorganic Chemistry, 57(9), 4966-4978. https://doi.org/10.1021/acs.inorgchem.7b03223
• Parker, D., Williams, J., & Walter, E. (2018). Tuning Mg2+ selectivity: comparative analysis of the photophysical properties of four fluorescent probes with an alkynyl-naphthalene fluorophore. Chemistry - A European Journal, 24(24), 6432-6441. https://doi.org/10.1002/chem.201800013
• Walter, E. R., Fox, M. A., Parker, D., & Williams, J. G. (2018). Enhanced selectivity for Mg2+ with a phosphinate-based chelate: APDAP versus APTRA. Dalton Transactions, 47(6), 1755-1763. https://doi.org/10.1039/c7dt04698g
• Walter, E. R., Williams, J. G., & Parker, D. (2017). Solvent polarity and oxygen sensitivity, rather than viscosity, determine lifetimes of biaryl-sensitised terbium luminescence. Chemical Communications, 53(100), 13344-13347. https://doi.org/10.1039/c7cc08361k
• Knuckey, K. J., & Williams, J. G. (2017). Photon Funnels for One-Way Energy Transfer: Multimetallic Assemblies Incorporating Cyclometallated Iridium or Rhodium Units Accessed by Sequential Cross-Coupling and Bromination. European Journal of Inorganic Chemistry, 2017(44), 5205-5214. https://doi.org/10.1002/ejic.201701020
• Maciejczyk, M. R., Williams, J. G., Robertson, N., & Pietraszkiewicz, M. (2017). Monothiatruxene: a new versatile core for functional materials. RSC Advances, 7(78), 49532-49535. https://doi.org/10.1039/c7ra07671a
• Mulla, R. S., Walden, M. T., Yufit, D. S., Desa, T., Lurie-Luke, E., & Williams, J. G. (2017). Strategies for the synthesis of HBGl3, a glutamic acid derived ligand bearing phenolic and azacarboxylate donor groups at the nitrogen atom. Tetrahedron, 73(45), 6410-6420. https://doi.org/10.1016/j.tet.2017.09.032
• Mulla, R., Pitarch-Jarque, J., Garcia-Espana, E., Desa, T., Lurie-Luke, E., & Williams, J. (2017). Monoamide Derivatives of EDTA Incorporating Pendent Carboxylates or Pyridyls: Synthesis, Metal Binding, and Crystal Structure of a Dinuclear Ca2+ Complex Featuring Bridging Na+ Ions. ChemistrySelect, 2(18), 5045-5050. https://doi.org/10.1002/slct.201700995
• Turnbull, G., Williams, J., & Kozhevnikov, V. (2017). Rigidly linking cyclometallated Ir(III) and Pt(II) centres: an efficient approach to strongly absorbing and highly phosphorescent red emitters. Chemical Communications, 53(18), 2729-2732. https://doi.org/10.1039/c7cc00656j
• Nisic, F., Cariati, E., Colombo, A., Dragonetti, C., Fantacci, S., Garoni, E., …Williams, J. (2017). Tuning the dipolar second-order nonlinear optical properties of 5-π-delocalized-donor-1,3-di(2-pyridyl) benzenes, related cyclometallated platinum(II) complexes and methylated salts. Dalton Transactions, 46(4), 1179-1185. https://doi.org/10.1039/c6dt04359c
• Shen, C., Srebro-Hooper, M., Jean, M., Vanthuyne, N., Toupet, L., Williams, J., …Crassous, J. (2017). Synthesis and Chiroptical Properties of Hexa-, Octa-, and Decaazaborahelicenes: Influence of Helicene Size and of the Number of Boron Atoms. Chemistry - A European Journal, 23(2), 407-418. https://doi.org/10.1002/chem.201604398
• McKenzie, L., Sazanovich, I., Baggaley, E., Bonneau, M., Guerchais, V., Williams, J., …Bryant, H. (2017). Metal Complexes for Two-Photon Photodynamic Therapy: A Cyclometallated Iridium Complex Induces Two-Photon Photosensitization of Cancer Cells under Near-IR Light. Chemistry - A European Journal, 23(2), 234-238. https://doi.org/10.1002/chem.201604792
• Moussa, J., Haddouche, K., Chamoreau, L., Amouri, H., & Williams, J. (2016). New N^C^N-coordinated Pd(ii) and Pt(ii) complexes of a tridentate N-heterocyclic carbene ligand featuring a 6-membered central ring: synthesis, structures and luminescence. Dalton Transactions, 45(32), https://doi.org/10.1039/c6dt02415g
• Daniels, R., Culham, S., Hunter, M., Durrant, M., Probert, M., Clegg, W., …Kozhevnikov, V. (2016). When two are better than one: bright phosphorescence from non-stereogenic dinuclear iridium(III) complexes. Dalton Transactions, 45(16), 6949-6962. https://doi.org/10.1039/c6dt00881j
• El Sayed Moussa, M., Chen, H., Wang, Z., Srebro-Hooper, M., Vanthuyne, N., Chevance, S., …Crassous, J. (2016). Bimetallic Gold(I) Complexes with Ethynyl-Helicene and Bis-Phosphole Ligands: Understanding the Role of Aurophilic Interactions in their Chiroptical Properties. Chemistry - A European Journal, 22(17), 6075-6086. https://doi.org/10.1002/chem.201600126
• Rodrigue-Witchel, A., Rochester, D. L., Zhao, S., Lavelle, K. B., Williams, J. G., Wang, S., …Reber, C. (2016). Pressure-induced variations of MLCT and ligand-centered luminescence spectra in square-planar platinum(II) complexes. Polyhedron, 108, 151-155. https://doi.org/10.1016/j.poly.2015.12.011
• Isla, H., Srebro-Hooper, M., Jean, M., Vanthuyne, N., Roisnel, T., Lunkley, J. L., …Crassous, J. (2016). Conformational changes and chiroptical switching of enantiopure bis-helicenic terpyridine upon Zn2+binding. Chemical Communications, 52(35), 5932-5935. https://doi.org/10.1039/c6cc01748g
• Moussa, J., Freeman, G. R., Williams, J. G., Chamoreau, L., Herson, P., & Amouri, H. (2016). Synthesis and Luminescence Properties of Cycloplatinated Complexes with a Chelating N∧C Pyridine-Derived N-Heterocyclic Carbene - Influence of 2,4,6-Triphenyl­phosphinine versus Triphenylphosphine. European Journal of Inorganic Chemistry, 2016(5), https://doi.org/10.1002/ejic.201500879
• Muñoz-Rodríguez, R., Buñuel, E., Fuentes, N., Williams, J., & Cárdenas, D. (2015). A heterotrimetallic Ir(III), Au(III) and Pt(II) complex incorporating cyclometallating bi- and tridentate ligands : simultaneous emission from different luminescent metal centres leads to broad-band light emission. Dalton Transactions, 44(18), 8394-8405. https://doi.org/10.1039/c4dt02761b
• Saleh, S., Moore, B., Srebro, M., Vanthuyne, N., Toupet, L., Williams, J., …Crassous, C. (2015). Acid/base-triggered switching of circularly polarized luminescence and electronic circular dichroism in organic and organometallic helicenes. Chemistry - A European Journal, 21(4), 1673-1681. https://doi.org/10.1002/chem.201405176
• Baggaley, E., Weinstein, J., & Williams, J. (2014). Time-resolved emission imaging microscopy using phosphorescent metal complexes: taking FLIM and PLIM to new lengths. Structure and bonding (Berlin. Internet), https://doi.org/10.1007/430_2014_168
• Moussa, J., Cheminel, T., Freeman, G., Chamoreau, L., Williams, J., & Amouri, H. (2014). An unprecedented cyclometallated platinum(II)complex incorporating a phosphinine co-ligand: synthesis and photoluminescence behaviour. Dalton Transactions, 43(22), 8162-8165. https://doi.org/10.1039/c4dt00589a
• Tarran, W., Freeman, G., Murphy, L., Benham, A., Kataky, R., & Williams, J. (2014). Platinum(II) Complexes of N^C^N‑Coordinating 1,3-Bis(2-pyridyl)benzene Ligands: Thiolate Coligands Lead to Strong Red Luminescence from Charge-Transfer States. Inorganic Chemistry, 53(11), 5738-5749. https://doi.org/10.1021/ic500555w
• Shen, C., Anger, E., Srebro, M., Vanthuyne, N., Deol, K., Jefferson, T., …Crassous, J. (2014). Straightforward access to mono- and biscycloplatinated helicenes displaying circularly polarized phosphorescence by using crystallization resolution methods. Chemical Science, 5(5), 1915-1927. https://doi.org/10.1039/c3sc53442a
• Baggaley, E., Botchway, S. W., Haycock, J. W., Morris, H., Sazanovich, I. V., Williams, J. G., & Weinstein, J. A. (2013). Long-lived metal complexes open up microsecond lifetime imaging microscopy under multiphoton excitation: from FLIM to PLIM and beyond. Chemical Science, 5(3), 879-886. https://doi.org/10.1039/c3sc51875b
• Anger, E., Rudolph, M., Norel, L., Zrig, S., Shen, C., Vanthuyne, N., …Réau, R. (2011). Multifunctional and Reactive Enantiopure Organometallic Helicenes: Tuning Chiroptical Properties by Structural Variations of Mono- and Bis(platinahelicene)s. Chemistry - A European Journal, 17(50), 14178-14198. https://doi.org/10.1002/chem.201101866
• Santoro, A., Prokhorov, A., Kozhevnikov, V., Whitwood, A., Donnio, B., Williams, J., & Bruce, D. (2011). Emissive Metallomesogens Based on 2-Phenylpyridine Complexes of Iridium(III). Journal of the American Chemical Society, 133(14), 5248-5251. https://doi.org/10.1021/ja201245s
• Kozhevnikov, D., Kozhevnikov, V., Shafikov, M., Prokhorov, A., Bruce, D., & Williams, J. (2011). Phosphorescence vs Fluorescence in Cyclometalated Platinum(II) and Iridium(III) Complexes of (Oligo) thienylpyridines. Inorganic Chemistry, 50(8), 3804-3815. https://doi.org/10.1021/ic200210e
• Murphy, L., Congreve, A., Pålsson, L., & Williams, J. (2010). The time domain in co-stained cell imaging: time-resolved emission imaging microscopy using a protonatable luminescent iridium complex. Chemical Communications, 46(46), 8743-8745. https://doi.org/10.1039/c0cc03705b
• Kalinowski, J., Cocchi, M., Virgili, D., Fattori, V., & Williams, J. (2006). Evidence for electric field dependent dissociation of exciplexes in electron donor-acceptor organic solid films. Chemical Physics Letters, 432(1-3), 110-115. https://doi.org/10.1016/j.cplett.2006.10.059
• Kruusma, J., Benham, A. M., Gareth Williams, J., & Kataky, R. (2006). An introduction to thiol redox proteins in the endoplasmic reticulum and a review of current electrochemical methods of detection of thiols. Analyst, 131(4), 459-473. https://doi.org/10.1039/b515874e
• Wilkinson, A., Puschman, H., Howard, J., Foster, C., & Williams, J. (2006). Luminescent Complexes of Iridium(III) Containing N∧C∧N-Coordinating Terdentate Ligands. Inorganic Chemistry, 45(21), 8685-8699. https://doi.org/10.1021/ic061172l
• Yin, B., Niemeyer, F., Williams, J., Jiang, J., Boucekkine, A., Toupet, L., …Guerchais, V. (2006). Synthesis, structure, and photophysical properties of luminescent platinum(II) complexes containing cyclometalated 4-styryl-functionalized 2-phenylpyridine ligands. Inorganic Chemistry, 45(21), 8584-8596. https://doi.org/10.1021/ic0607282
• Sénéchal-David, K., Hemeryck, A., Tancrez, N., Toupet, L., Williams, J., Ledoux, I., …Maury, O. (2006). Synthesis, structural studies, theoretical calculations, and linear and nonlinear optical properties of terpyridyl lanthanide complexes: New evidence for the contribution of f electrons to the NLO activity. Journal of the American Chemical Society, 128(37), 12243-12255. https://doi.org/10.1021/ja063586j
• Dias-Gunasekara, S., van Lith, M., Williams, J., Kataky, R., & Benham, A. (2006). Mutations in the FAD binding domain cause stress-induced misoxidation of the endoplasmic reticulum oxidoreductase Ero1b. Journal of Biological Chemistry, 281(35), 25018-25025. https://doi.org/10.1074/jbc.m602354200
• Arm, K., Leslie, W., & Williams, J. (2006). Synthesis and pH-sensitive luminescence of bis-terpyridyl iridium(III) complexes incorporating pendent pyridyl groups. Inorganica Chimica Acta, 359(4), 1222-1232. https://doi.org/10.1016/j.ica.2005.09.021
• Evans, R., Douglas, P., Williams, J., & Rochester, D. (2006). A novel luminescence-based colorimetric oxygen sensor with a "traffic light" response. Journal of Fluorescence, 16(2), 201-206. https://doi.org/10.1007/s10895-005-0037-9
• Virgili, D., Cocchi, M., Fattori, V., Sabatini, C., Kalinowski, J., & Williams, J. (2006). Highly efficient exciplex phosphorescence from organic light-emitting diodes. Chemical Physics Letters, 433(1-3), 145-149. https://doi.org/10.1016/j.cplett.2006.11.033
• Arm, K., & Williams, J. (2006). A cross-coupling strategy for the synthesis of dimetallic assemblies containing mixed bipyridine–terpyridine bridging ligands: luminescence and energy transfer properties. Dalton Transactions, 2172-2174. https://doi.org/10.1039/b602022d
• Dias-Gunasekara, S., Gubbens, J., van Lith, M., Dunne, C., Williams, J., Kataky, R., …Benham, A. (2005). Tissue-specific expression and dimerization of the endoplasmic reticulum oxidoreductase Erolb. Journal of Biological Chemistry, 280(38), 33066-33075. https://doi.org/10.1074/jbc.m505023200
• Bobba, G., Dickins, R., Kean, S., Mathieu, C., Parker, D., Peacock, R., …Geraldes, C. (2001). Chiroptical, ESMS and NMR spectroscopic study of the interaction of enantiopure lanthanide complexes with selected self-complementary dodecamer oligonucleotides. Journal of the Chemical Society-Perkin Transactions 2, 1729-1737
• Beeby, A., Faulkner, S., Parker, D., & Williams, J. (2001). Sensitised luminescence from phenanthridine appended lanthanide complexes: analysis of triplet mediated energy transfer processes in terbium, europium and neodymium complexes. Journal of the Chemical Society-Perkin Transactions 2, 1268-1273