General ILL seminar
organised by College 7
Tuesday, 9 December 2025 at 13h30
Seminar room 110-111, ILL 50, 1st floor
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“ Simultaneous neutron and optical studies ”
Stewart F. Parker
ISIS Facility, STFC Rutherford Appleton Laboratory, Chilton, Oxon, OX11 0QX, UK
Inelastic neutron scattering (INS) is a form of vibrational spectroscopy that excels in the detection of low energy modes, particularly those involving hydrogen. However, indirect geometry spectrometers such as Lagrange, TOSCA and VISION generally provide little useful information in the C=O stretch (1600 – 1800 cm-1) or the C–H/N–H/O–H stretch (2800 – 3600
cm-1) regions. While direct geometry instruments at spallation sources can access these regions, the resolution is modest and optical methods often provide better data. The desire for a wider spectral range coupled with a need to have a transferable method between techniques has led to the development of systems that allow simultaneous collection of Raman and INS data. In this talk I will describe three systems that are currently in use [1-3], some applications and the lessons learned, in particular, what to avoid!
I will also describe some recent work that builds on this experience that has led to the capability for in situ illumination of samples [4,5]. This has the goal of being able to measure the vibrational spectra of excited states by INS. I will conclude with my view of the prospects for simultaneous spectroscopic and neutron scattering studies.
References
[1] M.A. Adams, S.F. Parker, F. Fernandez-Alonso, D.J. Cutler, C. Hodges and A. King, Simultaneous neutron scattering and Raman scattering, Applied Spectroscopy 63 (2009) 727-732. [https://doi.org/10.1366/000370209788701107].
[2] S.K. Dugmore, Understanding chromotropic materials with combined insitu neutron diffraction and Raman spectroscopy, PhD thesis, Keele University, 2024.
[3] R.C. Gillis, Y.Q. Cheng, F.X. Gallmeier, M.A. Hartl, T. Huegle, E.B. Iverson, A sample holder for simultaneous Raman and neutron vibrational spectroscopy, Rev. Sci. Inst. 44 (2015) 7155–7176. [https://doi.org/10.1063/1.4997933]
[4] H. Cavaye and M. Schastny, In situ illumination with inelastic neutron scattering: a study of the photochromic material cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethene (CMTE), Phys. Chem. Chem. Phys. 23 (2021) 22324 - 22329. [https://doi.org/10.1039/d1cp03716a]
[5] D. Vong, E.C. Novak, A.J. Moulé and L.L. Daemen, Photochemistry sample sticks for inelastic neutron scattering, Rev. Sci. Inst. 94 (2023) 085102. [https://doi.org/10.1063/5.0154605]
Mohamed Zbiri (College 7 Secretary)
External visitors may ask for a site access to tellier(at)ill.fr