Jas Jayasooriya

Jas Jayasooriya


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Personal profile


School Position: Emeritus Reader in Chemistry.
Upali Jayasooriya was born in Kandy (Mahanuwara), the beautiful ancient hill capital of Sri Lanka. He gained his BSc in Chemistry with Physics from the University of Ceylon, Peradeniya, Sri Lanka (1968). MSc (1971) and PhD (1974) from the University of East Anglia under the supervision of the late Dr Don Powell. After a brief Lectureship at the University of Kelaniya, Sri Lanka and postdoctoral fellowships first at the University of East Anglia working jointly with Professors Norman Sheppard, Sid Kettle and Dr Don Powell and then at the University of Durham with the late Professor Tom Waddington, he was appointed in 1980 to an established Senior Research Fellowship at the University of East Anglia. He was subsequently appointed to lecturer in 1988 and to a Readership in 1999.

Novel chemical, analytical and biological applications of vibrational spectroscopy from the conventional IR and Raman spectroscopies to the relatively recent techniques of inelastic neutron scattering and nuclear inelastic scattering. Molecular magnetism using neutron scattering and muon spectroscopies. Electron and molecular dynamics of radical species generated by muon implantation. Applications to metallocenes and the problem of electron conduction in DNA. My research is carried out both at my laboratories at the University of East Anglia (IR and Raman spectroscopies) and in central facilities in Europe and USA (Neutron and Muon spectroscopies). These include ISIS at the Rutherford Appleton Laboratory in UK (http://www.isis.rl.ac.uk/); Institute Laue-Langevin and ESRF in Grenoble, France; Paul Scherrer Institute in Switzerland; and LANSC at the Los Alamos National Laboratory and APS at the Argonne National Laboratory, USA.

Selected Publications

Nuclear inelastic scattering spectroscopy of iron-sulfur cubane compounds
V.S. Oganesyan, J.E. Barclay, S.M. Hardy, D.J. Evans, C.J. Pickett and U.A. Jayasooriya
Chem. Commun., 2004, 214 – 215. 
DOI:  10.1039/b311279a

A strategy for the measurement of the vibrations of a muoniated radical centre: Experimental Evidence
U.A. Jayasooriya, F.L. Pratt, G.M. Aston, S. Hall, P.L. Hubbard and M. McCoustra
ChemPhysChem, 2004, 5, 257 – 261. 
DOI: 10.1002/cphc.200300832

Avoided level crossing muon spectroscopy of free radicals formed by muonium addition to the constituents of DNA
P.L. Hubbard, V.S. Oganesyan, N. Sulaimanov, J.M. Butt and U.A. Jayasooriya
J. Phys. Chem. A, 2004, 108, 9302 – 9309. 
DOI:  10.1021/jp0475335

Muon implantation of Metallocenes: Ferrocene
U.A. Jayasooriya, R. Grinter, P.L. Hubbard, G.M. Aston, J.A. Stride, G.A. Hopkins, L. Camus, I.D. Reid, S.P. Cottrell and S.F.J. Cox
Chem. Eur. J. 2007, 13, 2266-2276. 
DOI:  10.1002/chem.200600853

External Activities

  • 2006-08: Member of the organising committee of the “21st International Conference on Raman Spectroscopy - ICORS 2008”.
  • 2003-04-05 January: Lecturer at the EPSRC sponsored, Rutherford Laboratory run ‘Muon Training School’ for international researchers.
  • 2003 April: International examiner of a PhD examination panel at the University of Jaen, Spain
  • 2002 Nov: International examiner of a PhD examination panel at the Technical University of Delft, Holland
  • 1998 to 2001 : Member of the ‘International Selection Panel’ at the Institute Laue-Langevin, Grenoble, France
  • 2001 February: University of Bahrain, Bahrain. Invitation to assist in the organization of their Master of Science course.

Key Research Interests and Expertise

Vibrational Spectroscopy

The work has used the techniques of infrared, Raman, neutron scattering and nuclear inelastic scattering spectroscopies. The topics covered are:

  1. Development of symmetry based models for detailed understanding of the vibrations in the solid state, both for the internal and external modes. Probing different types of interactions found in the solids such as those between the internal modes of differently charged ions.
  2. Use of the metal cluster - surface analogy in vibrational spectroscopy to assign species found on catalytic surfaces. First conclusive evidence of surface modification due to adsorption of small molecules.
  3. Use of vibrational spectroscopy for the estimation of electron transfer rates in mixed valent systems.
  4. Analytical and chemical applications of FT-Raman spectroscopy. Pioneered the development of simultaneous Raman spectroscopic and differential scanning calorimetric measurements, both with FT-Raman and CCD-Raman. This provides unambiguous phase recognition and assignment in systems which show phase irreproducibility and uncertainty. This technique is presently providing unambiguous vibrational characterisation of different phases of materials of interest to food science such as trglycerides and cocoa butter.
  5. Single crystal Raman spectra of highly coloured compounds using FT-Raman spectroscopy.
  6. Nuclear inelastic scattering (NIS) spectroscopy is providing unique information on inter-ionic vibrational interactions.
  7. Vibrational spectroscopy in material science: the investigation of the mechanisms of formation of silicon oxycarbide glasses via sol-gel methods.

Oganesyan, V.S., Barclay, J.E., Evans, D.J., Darch, T., Marcer, C., Alp, E.E., & Jayasooriya, U.A.
Counterion effects in nuclear inelastic scattering spectroscopy, 2006.

Oganesyan, V.S., Barclay, J.E., Hardy, S.M., Evans, D.J., Darch, T., Pickett, C.J. & Jayasooriya, U.A.
Nuclear inelastic scattering spectroscopy of iron-sulfur cubane compounds.
Chem. Commun. 2004, 214-215.

Chomel, A.D., Dempsey, P., Latournerie, J., Hourlier-Bahloul, D. & Jayasooriya, U.A.
Gel to glass transformation of methyltriethoxysilane: A silicon oxycarbide glass precursor investigated using vibrational spectroscopy
Chem. Materials, 2005,
17, 4468-4473.

Brequel, H., Parmentier, J., Walter, S., Badheka, R., Trimmel, G., Masse, S., Latournerie, J., Dempsey, P., Turquat, C., Desmartin-Chomel, A., Le Neindre-Prum, L., Jayasooriya, U.A., Hourlier, D., Kleebe, H.J., Soraru, G.D., Enzo, S., Babonneau, F.
Systematic structural characterisation of the high-temperature behaviour of nearly stoichiometric silicon oxycarbide glasses.
Chem. Materials, 2004, 16, 2585-2598.

Clayden, N.J., Esposito, S., Jayasooriya, U.A., Sprunt, J. & Pemice, P.
Solid state Si-29 NMR and FT Raman spectroscopy of the devitrification of lithium metasilicate glass.
Journal of Non-Crystalline Solids, 1998, 224, 50-56.

Parker, S.F., Jayasooriya, U.A., Sprunt, J.C., Bortz, M. & Yvon, K. 
Inelastic neutron scattering, IR and Raman spectroscopic studies of Mg2CoH5 and Mg2CoD5.
Journal of the Chemical Society-Faraday Transactions, 1998, 94, 2595-2599.

OmApinyan, S., Rajmankina, T., delaCruz, C. & Jayasooriya, U.A.
Fourier-transform surface enhanced Raman scattering: A quantitative technique?
Spectrochimica Acta Part A - Molecular and Bimolecular Spectroscopy, 1997, 53, 877-879.

Sprunt, J. & Jayasooriya, U.A.
Simultaneous FT-Raman differential scanning calorimetry measurements using a low-cost fibre-optic probe.
Journal of Applied Spectroscopy, 1997, 51, 1410-1414.

Parker, S.F. & Jayasooriya, U.A.
The determination of the geometry of surface species by vibrational spectroscopy: Application to ethylidyne.
Surface Science, 1996, 368, 275-278.

Jayasooriya, U.A., Kettle, S.F.A, Mahasuverachai, S., & White, R.P.
Lattice vibrations in compounds crystallising with the baryte structure.
J. Chem. Soc. Faraday Trans. 1996, 92, 3625-3628.

Wu, R., Arap Koske, S.K., White, R.P., Anson, C.E., Jayasooriya, U.A. & Cannon, R.D.
Electron Transfer Rates in a Trinuclear Mixed-Valence Iron(III,III,II) Molecule: a Variable-Temperature Infrared Spectroscopic Study.
J. Chem. Soc., Chem. Commun., 1994, 1657-1658.

Jayasooriya, U.A.
Vibrational spectroscopic analysis of group 6 metal hexacarbonyls in the solid state.
J. Chem. Soc. Faraday Trans., 1994, 90, 1265-1269 .

Jayasooriya, U.A., Anson, C.E., Al-Jowder O., D'Alfonso, G., Stanghellini, P.L. & Rossetti, R.
Vibrational spectra of methoxy ligands on metal clusters: Modelling methoxy groups on copper single crystal surfaces.
Surface Science, 294, 1993, 131-140.

Harju, M.E.E., Valkonnen, J., Jayasooriya, U.A. & Wolverson, D.
Simultaneous application of charge coupled device array-detected Raman spectroscopy and differential scanning calorimetry to in situ investigation of phase transitions in condensed matter.
J. Chem. Soc. Farad. Trans., 1992, 88, 2717.

Harju, M.E.E., Valkonnen, J. & Jayasooriya, U.A.
Simultaneous application of Fourier transform Raman spectroscopy and differential scanning calorimetry for the in situ investigation of phase transitions in condensed matter.
Spectrochim. Acta., 1991, 47A, 1395.

Jayasooriya, U.A. & Kettle, S.F.A. Lattice vibrations in relatively complicated crystal structures: aragonite.
Phys.Rev. B., 1984, 29(4), 2227.

Durman, R., Jayasooriya, U.A., Kettle, S.F.A., Mahasuverachai, S., Mortimer, R., & Norrby, L-J
Factor group splitting and dispersion on internal vibrational modes: a qualitative discussion.
Chem. Phys.,
1984, 81, 5247.

Jayasooriya, U.A., Chesters, M.A., Howard, M. W., Kettle, S.F.A., Powell, D.B. & Sheppard, N.
Vibrational spectroscopic characterisation of hydrogen bridges between metal atoms: a model for the adsorption of hydrogen on low-indexed faces of tungsten.
Surface Science 93, 1980, 526.


The research on magnetism is with the use of inelastic neutron scattering spectroscopy, which has been used to study a series of polymetallic systems. Exchange interactions were measured and small molecular distortions estimated by measuring the splitting of the electronic ground state. Number of systems which appeared to be trigonally symmetrical when analysed by diffraction techniques, were shown in fact to be distorted, implying the presence of a magnetic Jahn-Teller effect. Our recent work suggests the possibility of using proton tunnelling, observable with neutron scattering, as a probe of the packing forces in the solid state. This should thus provide a way of unambiguously assigning distortions to the Magnetic-Jahn-Teller effect, which has eluded the researchers up to now.

Further magnetic work is being done with polarised neutron diffraction, a technique which gives accurate estimates of spin density distributions in solid state systems.

Stride, J.A., Jayasooriya, U.A. & Eckert, J.
Dynamics of ligated water molecules in oxo-centered trinuclear carboxylates: An incoherent inelastic neutron scattering study.
Angewandte Chemie-International Edition 38, 1999, 116-121.

Cannon, R.D., Jayasooriya, U.A., Sowrey, F.E., Tilford, C., Little, A., Bourke, J.P., Rogers, R.D., Vincent, J.B. & Kearley, G.J.
Concealed asymmetry in an exchange-coupled trichromium(lll) cluster: Structure and magnetic spectrum of [Cr3O9OOCPh)(6)(py)(3)](py)(0.5)CIO4.
Inorganic Chemistry 37, 1998, 5675-5678.

Wu, R.W., Poyraz, M., Sowrey, F.E., Anson, C.E., Wocadlo, S., Powell, A.K., Jayasooriya, U.A., Cannon, R.D., Nakamoto, T., Katada, M. & Sano, H.
Electron localization and delocalization in mixed-valence transition metal clusters: Structural and spectroscopic studies of oxo-centered trinuclear complexes [Fe3O(OOCCMe3)6(py)3](+/O) and [Mn3O(OOCCMe3)6(py)3](+/O).
Inorganic Chemistry 37,1998, 1913-1921.

Cannon, R.D., Jayasooriya, U.A.,Wu, R., arapKoske, S.K., Stride, J.A., Nielsen, O.F., White, R.P., Kearley, G.J. & Summerfield, D.
Spin Frustration in High-Spin Triiron(III) Complexes: an Inelastic Neutron Scattering Study.
J. Am. Chem. Soc. 116, 1994, 11869.

White, R.P., Stride, J.A., Bollen, S.K., Chai Sa-ard, N., Kearley, G.J., Jayasooriya, U.A. & Cannon, R.D.
Electronic Interactions in Mixed-Valence and Mixed-Metal Ion Clusters: Inelastic Neutron Scattering Spectra of the Complexes [FeIII2MIIO(O2CMe)6(py)3] (py), where M = Mn, Ni.
J. Am. Chem. Soc. 115, 1993, 7778-7782.

Jayasooriya, U.A., Cannon, R.D., White, R.P., Stride, J.A., Grinter, R., & Kearley, G.J.
Exchange Interactions in Trinuclear Basic Chromium(III) Clusters: Direct Observation of the Magnetic Spectrum by Inelastic Neutron Scattering.
J. Chem. Phys. 98, 1993, 9303-9310.

Cannon, R.D., Jayasooriya, U.A., Anson, C.E., White, R.P., Tasset, F., Ballou, R. & Rosseinsky, D.R.J.
Direct observation of electron localisation in a mixed-valence double salt: a polarised neutron diffraction study of K3(MnO4)2.
Chem. Soc., Chem. Commun. 1445, 1992.

Muon Spectroscopy

Our latest interest is in the applications of muon spectroscopy to chemical problems, some pioneering investigations into muon implantations in inorganic and organometallic systems. The MuSR studies cover molecular dynamics, electron dynamics and magnetic phase changes. Some of these studies have been reported as posters in several of the international conferences and meetings. Some of our work on molecular dynamics with MuSR have been highlighted by the Rutherford Appleton Laboratory of the Engineering and Physical Sciences Research Council, UK, in its annual report (1995) 97. One objective is to measure the vibrational spectrum of a muonated centre.

Jayasooriya, U.A., Grinter, R., Hubbard, P.L., Aston, G.M., Stride, J.A., Hopkins, G.A., Camus, L., Reid, I.D., Cottrell, S.P. & Cox, S.F.J.
Muon implantation of Metallocenes: Ferrocene.
Chemistry. 2007;13(8):2266-76.

Hubbard, P.L., Tani, A., Oganesyan, V.S., Butt, J.N., Cottrell, S.P. & Jayasooriya, U.A.
Different responses to muon implantation in single- and double-stranded DNA.
Physica B-Cond. Matter, 2006, 374, 437-440.

Hubbard, P.L., Oganesyan, V.S., Sulaimanov, N., Butt, J.M. & Jayasooriya U.A.
Avoided level crossing muon spectroscopy of free radicals formed by muonium addition to the constituents of DNA.
J. Phys. Chem. A, 2004, 108, 9302 – 9309.

Jayasooriya, U.A., Pratt, F.L., Aston, G.M., Hall, S., Hubbard P.L. & McCoustra, M.
A strategy for the measurement of the vibrations of a muoniated radical centre: Experimental Evidence.
ChemPhysChem, 2004, 5, 257–261.

Stride, J.A., Jayasooriya, U.A. & Reid, I.D.
Muon spin rotation of carbonyl compounds, an exploration of the mechanism of hyperfine interaction.
J. Phys. Chem.A, 2002, 106(2):244-250.

Jayasooriya, U.A., Aston, G.M., Stride, J.A.
Molecular dynamics of organometallic compounds using mSR.
Applied Magnetic Resonance, 1997, 13, 165. 

Jayasooriya, U.A., Stride, J.A., Aston, G.M., Hopkins, G.A., Cox, S.F.J. & Scott, C.A.
Muon spin relaxation as a probe of molecular dynamics of organometallic compounds.
Hyperfine Interactions 106, 1997, 27-32.

Aston, G.M., Stride, J.A., Jayasooriya, U.A. & Reid, I.D.
The hyperfine coupling tensors of muonated radicals in single-crystal benzophenone.
Hyperfine Interactions 106, 1997, 157-162.

Current Research Projects

  • Measurement of the vibrations of muonated centres in muonated/muniated radicals. [CCLRC funded]
  • Development of an RF-MuSR facility at the Rutherford Appleton Laboratory and the study of radical kinetics including those of enediyne antitumor antibiotics. [CCLRC funded]
  • Molecular dynamics with MuSR of organometallics with particular reference to metallocene catalysts. [CCLRC funded]
  • mSR studies of electron conduction in DNA. [EPSRC funded]
  • Applications of atom specific methods of vibrational spectroscopy to chemical and analytical problems. [EPSRC funded]
  • Exploring the use of natural isotope abundance in authentication from a vibrational spectroscopic view point. [Funded by ICENI]

Research Funding 

A method for detecting and assigning of muon-molecule diamagnetic species?
Rutherford Appleton Lab contract
Jayasooriya, UA
20-Sep-06 - 19-March-07

The development of the chemical applications of muon magnetic resonance
Jayasooriya, UA
01-Jun-06 - 31-May-08

Muon spectroscopy of flames
Rutherford Appleton Lab contract
Jayasooriya, UA and Ashworth, SH
11-Feb-05 - 31-Dec-07

Rotational optic lattice modes in NIS spectroscopy of molecules containing off centre iron atoms
Jayasooriya, UA and Oganesyan, VS
11-Jan-06 - 10-Jul-06

Molecular and electron dynamics of one-dimensional liquid crystals
Rutherford Appleton Lab contract
Jayasooriya, UA and Cammidge, AN
11-Feb-05 - 10-Feb-06

Laying the foundation for a rf-musr-laser vibrational spectroscopy experiment
Rutherford Appleton Lab contract
Jayasooriya, UA
11-Feb-05 - 10-Feb-06

Assessment of the incorporation of steroidal drug molecules into liposomes using ?SR
Rutherford Appleton Lab contract
Jayasooriya, UA and Barker, SA
11-Feb-05 - 10-Feb-06

Development of scientific applications of radio frequency muon spin resonance, – Commissioning the new RF spectrometer
Cottrell S.P. (RAL); Jayasooriya UA; Clayden JC
01-Oct-01 – 30-Aug-04
£331,101 (RAL)

Electron transfer mediated magnetic ordering in an outer space sphere mixed valence compound
Jayasooriya, UA
30-Oct-01 - 06-Aug-03

(a) Muon Spectroscopies as a probe of electron conduction in DNA, and (b) Muon spectroscopy of organometallics
Jayasooriya, UA and Butt, JN
08-Aug-01 - 07-Nov-02

Resonance Raman gas sensors
Jayasooriya, UA and Cammidge, AN
06-Jul-98 -05-Apr-02

CEC (Universite Pierre et Marie Curie, Paris)
Design and characterization of chemically derived silicon oxycarbide glasses with enhanced high temperature properties
Jayasooriya, UA and Gilkes, K
01-Mar-98 - 28-Feb-02

Royal Society of Chemistry
Studentship: Stable isotope resonance Raman spectroscopy
Jayasooriya, UA
01-Oct-98 - 30-Sep-01


Chemical and analytical applications of infrared and Raman spectroscopes; neutron scattering; muon spin rotation, relaxation and resonance; nuclear inelastic scattering or nuclear resonance vibrational spectroscopy.