Publications – Ultrafast Molecular Dynamics

2026

A. M. Ghrist, M. Bain, Y. Liu, W. O. Razmus, S. Bhattacharyya, K. Chen, I. Gabalski, J. M. Glownia, A. E. Green, B. Kaufman, P. L. Kramer, K. A. Larsen, M. P. Minitti, A. J. Orr-Ewing, A. H. Reid, D. Rolles, J. Searles, D. Townsend, T. J. A. Wolf, T. Xu, B. F. E. Curchod, M. N. R. Ashfold, P. H. Bucksbaum, F. Allum, R. S. Minns & R. Forbes, Resolving competing ultraviolet photoinduced ring-opening and dissociation pathways in iodothiophenes by ultrafast electron diffraction, J. Phys. Chem. Lett., doi.org/10.1021/acs.jpclett.6c01596, (2026).

L. Ireland, R. Anderson, J. M. Żurek, M. J. Paterson, C. Sparling & D. Townsend, Tomographic reconstruction of photoelectron elliptical dichroism in chiral terpenes and terpenoids, J. Chem. Phys., 165, 074303, (2026).

2025

S. L. Jackson, A. W. Prentice, L. Bertram, L. Hutton, N. Kotsina, C. Brahms, C. Sparling, J. C. Travers, A. Kirrander, M. J. Paterson & D. Townsend, Decoupling structural molecular dynamics from excited state lifetimes using few-femtosecond ultraviolet resonant dispersive waves, Nat. Commun., 16, 9986, (2025).

R. Montero, I. Lamas, M. Fernández-Fernández, A. W. Prentice, D. Townsend, M. J. Paterson & A. Longarte, Relaxation dynamics of aniline in methanol: The photoionization channel, Phys. Chem. Chem. Phys., 27, 15574, (2025).

C. Sparling & D. Townsend, Two decades of imaging photoelectron circular dichroism: from first principles to future perspectives, Phys. Chem. Chem. Phys., 27, 2888, (2025).

M. Garrow, L. Bertram, A. Winter, A. W. Prentice, S. W. Crane, P. D. Lane, S. W. Greaves, M. J. Paterson, A. Kirrander & D. Townsend, Excited state dynamics of azanaphthalenes reveal opportunities for the rational design of photoactive molecules, Commun. Chem., 8, 7, (2025). 2025 Editors’ Highlight.

I. Powis, D. A. Shaw, D. Townsend & D. M. P. Holland, Valence shell electronically excited states of 1-phenylimidazole and 1-benzylimidazole, Mol. Phys., 123, e2353878, (2025).

2024

C. Sparling, D. Rajak, V. Blanchet, Y. Mairesse & D. Townsend, Fourier-Hankel-Abel Nyquist-limited Tomography: A spherical harmonic basis function approach to tomographic velocity-map image reconstruction, Rev. Sci. Instrum., 95, 053301, (2024).

W. O. Razmus, F. Allum, J. Harries, Y. Kumagai, K. Nagaya, S. Bhattacharyya, M. Britton, M. Brouard, P. H. Bucksbaum, K. Cheung, S. W. Crane, M. Fushitani, I. Gabalski, T. Gejo, A. Ghrist, D. Heathcote, Y. Hikosaka, A. Hishikawa, P. Hockett, E. Jones, E. Kukk, H. Iwayama, H. V. S. Lam, J. W. McManus, D. Milesevic, J. Mikosch, S. Minemoto, A. Niozu, A. J. Orr-Ewing, S. Owada, D. Rolles, A. Rudenko, D. Townsend, K. Ueda, J. Unwin, C. Vallance, A. Venkatachalam, S. Wada, T. Walmsley, E. M. Warne, J. L. Woodhouse, M. Burt, M. N. R. Ashfold, R. S. Minns & R. Forbes, Exploring the ultrafast and isomer-dependent photodissociation of iodothiophenes via site-selective ionization, Phys. Chem. Chem. Phys., 26, 12725, (2024).

2023

C. Sparling, A. Ruget, L. Ireland, N. Kotsina, O. Ghafur, J. Leach & D. Townsend, The importance of molecular axis alignment and symmetry-breaking in photoelectron elliptical dichroism, J. Chem. Phys., 159, 214301, (2023).

S. W. Crane, M. Garrow, P. D. Lane, K. Robertson, A. Waugh, J. M. Woolley, V. G. Stavros, M. J. Paterson, S. J. Greaves & D. Townsend, The value of different experimental observables: A transient absorption study of the ultraviolet excitation dynamics operating in nitrobenzene, J. Phys. Chem. A., 127, 6425, (2023).

D. Townsend, Mapping extended reaction coordinates in photochemical dynamics, J. Mol. Spec., 395, 111807, (2023).

D. M. P. Holland, D. A. Shaw, D. Townsend & I. Powis, Valence shell electronically excited states of imidazole and 1-methylimidazole, Mol. Phys., 121, e2122614, (2023).

C. Sparling, S. W. Crane, L. Ireland, R. Anderson, O. Ghafur, J. B. Greenwood & D. Townsend, Velocity-map imaging of photoelectron circular dichroism in non-volatile molecules using a laser-based desorption source, Phys. Chem. Chem. Phys., 25, 6009, (2023). PCCP HOT Article.

2022

N. Kotsina, S. L. Jackson, T. Malcomson, M. J. Paterson & D. Townsend, Photochemical carbon–sulfur bond cleavage in thioethers mediated via excited state Rydberg-to-valence evolution, Phys. Chem. Chem. Phys., 24, 29423, (2022). PCCP HOT Article.

C. Sparling & D. Townsend, Tomographic reconstruction techniques optimized for velocity-map imaging applications, J. Chem. Phys., 157, 114201, (2022).

N. Kotsina, C. Brahms, S. L. Jackson, J. C. Travers & D. Townsend, Spectroscopic application of few-femtosecond deep-ultraviolet laser pulses from resonant dispersive wave emission in a hollow core capillary, Chem. Sci., 13, 9585, (2022).

C. Sparling, A. Ruget, J. Leach & D. Townsend, Arbitrary Image Reinflation: A deep learning technique for recovering 3D photoproduct distributions from a single 2D projection, Rev. Sci. Instrum., 93, 023303, (2022).

2021

L. Saalbach, N. Kotsina, S. W. Crane, M. J. Paterson & D. Townsend, Ultraviolet excitation dynamics of nitrobenzenes, J. Phys. Chem. A, 125, 7174, (2021).

J. Bocková, A. Rebelo, M. Ryszka, R. Pandey, D. Mészáros, P. Limão-Vieira, P. Papp, N. J. Mason, D. Townsend, K. L. Nixon, V. Vizcaino, J.-C. Poully & S. Eden, Thermal desorption effects on fragment ion production from multi-photon ionized uridine and selected analogues, RSC Adv., 11, 20612, (2021).

N. Kotsina & D. Townsend, Improved insights in time-resolved photoelectron imaging, Phys. Chem. Chem. Phys., 23, 10736, (2021).

C. Sparling, A. Ruget, N. Kotsina, J. Leach & D. Townsend, Artificial neural networks for noise removal in data‐sparse charged particle imaging experiments, ChemPhysChem, 22, 76, (2021).

2020

M. J. Paterson & D. Townsend, Rydberg-to-valence evolution in excited state molecular dynamics, Int. Rev. Phys. Chem., 39, 517, (2020).

N. Kotsina, M. Candelaresi, L. Saalbach, M. M. Zawadzki, S. W. Crane, C. Sparling & D. Townsend, Short-wavelength probes in time-resolved photoelectron spectroscopy: An extended view of the excited state dynamics in acetylacetone, Phys. Chem. Chem. Phys., 22, 4647, (2020).

S. W. Crane, O. Ghafur, L. Saalbach, M. J. Paterson & D. Townsend, The influence of substituent position on the excited state dynamics operating in 4-, 5- and 6-hydroxyindole, Chem. Phys. Lett., 738, 136870, (2020). Editor’s Choice.

2019

I. Lamas, A. Longarte, A. Peralta Conde, G. Muga, D. Townsend & R. Montero, Dynamics of pyrroles excited to the 3s/πσ* state, J. Phys. Chem. A, 123, 8980, (2019).

S. W. Crane, O. Ghafur, T. Y. Cowie, A. G. Lindsay, J. O. F. Thompson, J. B. Greenwood, M. W. P. Bebbington & D. Townsend, Dynamics of electronically excited states in the eumelanin building block 5,6-dihydroxyindole, Phys. Chem. Chem. Phys., 21, 8152, (2019).

M. A. B. Larsen, T. I. Sølling, R. Forbes, A. E. Boguslavskiy, V. Makhija, K. Veyrinas, R. Lausten, A. Stolow, M. M. Zawadzki, L. Saalbach, N. Kotsina, M. J. Paterson & D. Townsend, Vacuum ultraviolet excited state dynamics of small amides, J. Chem. Phys., 150, 054301, (2019).

N. Kotsina, F. Belli, S. -f. Gao, Y. -y. Wang, P. Wang, J. C. Travers & D. Townsend, Ultrafast molecular spectroscopy using a hollow-core photonic crystal fiber light source, J. Phys. Chem. Lett., 10, 715, (2019).

2018

O. Ghafur, S. W. Crane, M. Ryszka, J. Bockova, A. Rebelo, L. Saalbach, S. De Camillis, J. B. Greenwood, S. Eden & D. Townsend, Ultraviolet relaxation dynamics in uracil: Time-resolved photoion yield studies using a laser-based thermal desorption source, J. Chem. Phys., 149, 034301, (2018). JCP Editors’ Choice 2018.

O. Schalk, D. Townsend, T. J. A. Wolf, D. M. P. Holland, A. E. Boguslavskiy, M. Szöri & A. Stolow, Time-resolved photoelectron spectroscopy of nitrobenzene and its aldehydes, Chem. Phys. Lett., 691, 379, (2018).

2017

N. Kotsina & D. Townsend, Relative detection sensitivity in ultrafast spectroscopy: state lifetime and laser pulse duration effects, Phys. Chem. Chem. Phys., 19, 29409, (2017).

J. Miles, D. Fernandes, A. Young, C. M. M. Bond, S. W. Crane, O. Ghafur, D. Townsend, J. Sá & J. B. Greenwood, A new technique for probing chirality via photoelectron circular dichroism, Anal. Chim. Acta, 984, 134, (2017).

2016

S. W. Crane, M. M. Zawadzki, J. O. F. Thompson, N. Kotsina, O. Ghafur & D. Townsend, Caveats in the interpretation of time-resolved photoionization measurements: A photoelectron imaging study of pyrrole, J. Chem. Phys., 145, 234304, (2016).

M. M. Zawadzki, M. Candelaresi, L. Saalbach, S. W. Crane, M. J. Paterson & D. Townsend, Observation of multi-channel non-adiabatic dynamics in aniline derivatives using time-resolved photoelectron imaging, Faraday Discuss., 194, 185, (2016).

T. F. M. Luxford, T. R. Sharples, D. Townsend, K. G. McKendrick & M. L. Costen, Comparative stereodynamics in molecule-atom and molecule-molecule rotational energy transfer: NO(A²Σ⁺) + He and D₂, J. Chem. Phys., 145, 084312, (2016).

L. B. Klein, J. O. F. Thompson, S. W. Crane, L. Saalbach, T. I. Sølling, M. J. Paterson & D. Townsend, Ultrafast relaxation dynamics of electronically excited piperidine: ionization signatures of Rydberg/valence evolution, Phys. Chem. Chem. Phys., 18, 25070, (2016).

L. B. Klein, T. J. Morsing, R. A. Livingstone, D. Townsend & T. I. Sølling, The effects of symmetry and rigidity on non-adiabatic dynamics in tertiary amines: a time-resolved photoelectron velocity-map imaging study of the cage-amine ABCO, Phys. Chem. Chem. Phys., 18, 9715, (2016).

J. O. F. Thompson, L. B. Klein, T. I. Sølling, M. J. Paterson & D. Townsend, The role of novel Rydberg-valence behaviour in the non-adiabatic dynamics of tertiary aliphatic amines, Chem. Sci., 7, 1826, (2016).

Earlier Papers

T. R. Sharples, T. F. M. Luxford, D. Townsend, K. G. McKendrick & M. L. Costen, Rotationally inelastic scattering of NO(A²Σ⁺) + Ar: Differential cross sections and rotational angular momentum polarization, J. Chem. Phys., 143, 204301, (2015).

M. M. Zawadzki, J. O. F. Thompson, E. A. Burgess, M. J. Paterson & D. Townsend, Time-resolved photoionization spectroscopy of mixed Rydberg-valence states: indole case study, Phys. Chem. Chem. Phys., 17, 26659, (2015).

S. De Camillis, J. Miles, G. Alexander, O. Ghafur, I. D. Williams, D. Townsend & J. B. Greenwood, Ultrafast non-radiative decay of gas-phase nucleosides, Phys. Chem. Chem. Phys., 17, 23643, (2015).

J. O. F. Thompson, L. Saalbach, S. W. Crane, M. J. Paterson & D. Townsend, Ultraviolet relaxation dynamics of aniline, N,N-dimethylaniline and 3,5-dimethylaniline at 250 nm, J. Chem. Phys., 142, 114309, (2015).

S. E. Greenough, M. D. Horbury, J. O. F. Thompson, G. M. Roberts, T. N. V. Karsili, B. Marchetti, D. Townsend & V. G. Stavros, Solvent induced conformer specific photochemistry of guaiacol, Phys. Chem. Chem. Phys., 16, 16187, (2014).

J. O. F. Thompson, R. A. Livingstone & D. Townsend, Following the relaxation dynamics of photoexcited aniline in the 273-266 nm region using time-resolved photoelectron imaging, J. Chem. Phys., 139, 034316, (2013).

A. S. Chatterley, J. D. Young, D. Townsend, J. M. Žurek, M. J. Paterson, G. M. Roberts & V. G. Stavros, Manipulating dynamics with chemical structure: probing vibrationally-enhanced tunnelling in photoexcited catechol, Phys. Chem. Chem. Phys., 15, 6879, (2013).

R. A. Livingstone, J. O. F. Thompson, M. Iljina, R. J. Donaldson, B. J. Sussman, M. J. Paterson & D. Townsend, Time-resolved photoelectron imaging of excited state relaxation dynamics in phenol, catechol, resorcinol and hydroquinone, J. Chem. Phys., 137, 184304, (2012).

E. Rubino, J. McLenaghan, S. C. Kehr, F. Belgiorno, D. Townsend, S. Rohr, C. E. Kuklewicz, U. Leonhardt, F. König & D. Faccio, Negative-frequency resonant radiation, Phys. Rev. Lett., 108, 253901, (2012).

R. Livingstone, O. Schalk, A. E. Boguslavskiy, G. Wu, L. T. Bergendahl, A. Stolow, M. J. Paterson & D. Townsend, Following the relaxation dynamics of indole and 5-hydroxyindole using time-resolved photoelectron spectroscopy, J. Chem. Phys., 135, 194307, (2011).

P. J. Bustard, G. Wu, R. Lausten, D. Townsend, I. A. Walmsley, A. Stolow & B. J. Sussman, From molecular control to quantum technology with the dynamic Stark effect, Faraday Discuss., 153, 321, (2011).

A. E. Boguslavskiy, M. S. Schuurman, D. Townsend & A. Stolow, Non-Born-Oppenheimer wavepacket dynamics in polyatomic molecules: vibrations at conical intersections in DABCO, Faraday Discuss., 150, 419, (2011).

D. Townsend, B. J. Sussman & A. Stolow, A Stark future for quantum control, J. Phys. Chem. A, 115, 357, (2011).

P. Hockett, M. Staniforth, K. L. Reid, & D. Townsend, Rotationally resolved photoelectron angular distributions from a nonlinear polyatomic molecule, Phys. Rev. Lett., 102, 253002, (2009).

H. R. Hudock, B. G. Levine, A. L. Thompson, H. Satzger, D. Townsend, N. Gador, S. Ullrich, A. Stolow & T. J. Martinez, Ab initio molecular dynamics and time resolved photoelectron spectroscopy of electronically excited uracil and thymine, J. Phys. Chem. A, 111, 8500, (2007).

D. Townsend, H. Satzger, T. Ejdrup, A. M. D. Lee, H. Staplefeldt & A. Stolow, ¹B₂ (¹Σ_u⁺) excited state decay dynamics in CS₂, J. Chem. Phys., 125, 234302, (2006).

B. J. Sussman, D. Townsend, M. Yu. Ivanov & A. Stolow, Dynamic Stark control of photochemical processes, Science, 314, 278, (2006).

H. Satzger, D. Townsend & A. Stolow, Reassignment of the low-lying cationic states in gas-phase adenine and 9-methyl adenine, Chem. Phys. Lett., 430, 144, (2006).

S. A. Lahankar, S. D. Chambreau, D. Townsend, F. Suits, J. Farnum, X. Zhang, J. M. Bowman & A. G. Suits, The roaming atom pathway in formaldehyde decomposition, J. Chem. Phys., 125, 044303, (2006).

H. Satzger, D. Townsend, M. Z. Zigerski, S. Patchkovskii, S. Ullrich & A. Stolow, Primary processes underlying the photostability of isolated DNA bases: Adenine, Proc. Natl. Acad. Sci. USA, 103, 10196, (2006).

S. D. Chambreau, D. Townsend, S. A. Lahankar, S. K. Lee & A. G. Suits, Novel molecular elimination in formaldehyde photodissociation: The roaming H atom pathway, Phys. Scr., 73, C89, (2006).

D. Townsend, W. Li, S. K. Lee, R. L. Gross & A. G. Suits, Universal and state resolved imaging of chemical dynamics, J. Phys. Chem. A, 109, 8661, (2005).

S. K. Lee, D. Townsend, O. S. Vasyutinskii & A. G. Suits, O(¹D₂) orbital orientation in the ultraviolet photodissociation of ozone, Phys. Chem. Chem. Phys., 7, 1650, (2005).

D. Townsend, S. A. Lahankar, S. K. Lee, S. D. Chambreau, A. G. Suits, X. Zhang, J. Rheinecker, L. B. Harding & J. M. Bowman, The roaming atom: Straying from the reaction path in formaldehyde decomposition, Science, 306, 1158, (2004).

D. Townsend, S. K. Lee & A. G. Suits, DC slice imaging of CH₃Cl photolysis at 193.3 nm, J. Phys. Chem. A, 108, 8106, (2004).

D. Townsend, S. K. Lee & A. G. Suits, Orbital polarization from DC slice imaging: S(¹D₂) alignment in the photodissociation of ethylene sulfide, Chem. Phys., 301, 197, (2004).

D. Townsend, M. P. Minitti & A. G. Suits, Direct current slice imaging, Rev. Sci. Instrum., 74, 2530, (2003).

R. A. L. Smith, V. G. Stavros, J. R. R. Verlet, H. H. Fielding, D. Townsend & T. P. Softley, The role of phase in molecular Rydberg wavepacket dynamics, J. Chem. Phys., 119, 3085, (2003).

D. Townsend, A. L. Goodgame, S. R. Procter, S. R. Mackenzie & T. P. Softley, Deflection of krypton Rydberg atoms in the field of an electric dipole, J. Phys. B: At. Mol. Opt. Phys., 34, 439, (2001).

D. Townsend, & K. L. Reid, Photoionization dynamics probed by angle-resolved photoelectron spectroscopy of NH₃ (B¹E”), J. Chem. Phys., 112, 9783, (2000).