Ultrafast dynamics in molecules
15 Jan 2021



Artemis has two experimental chambers for studies of molecular targets in the gas or liquid phase.




Gas-phase AMO end-station 

Artemis has the ability to study atoms and small molecules in the gas phase with ultrafast time resolutions (<50 fs). Ultrafast dynamics are studied using photoelectron techniques: either high-resolution time-of-flight detectors or velocity-map imaging techniques to give angular information. 

One of our key experimental techniques is UV-pump XUV-probe photoelectron spectroscopy with a tuneable UV pump and an XUV probe, which enables us to explore the photodissociation dynamics of small molecules [1,2,3]. This techniques makes use of the Artemis gas-phase AMO end-station coupled to the 1 kHz XUV beamline, with HHG generated from either 800 nm or 400 nm pulses.  ​​

Other recent experiments using this end-station have explored Coulomb explosion imaging [4,5], and multiphoton photoelectron circular dichroism [6​]. 

Pump-probe photoelectron spectrum in CS2, from [1]. False color surface map showing the changes in the background-subtracted photoelectron spectrum as a function of the pump-probe time delay.

The gas-phase AMO end station is comprised of two coupled chambers. The upper chamber can either be configured to take a range of VMI configurations or can be equipped with a Kaesdorf ETF11 TOF spectrometer. The lower chamber is the gas source, which can be either a pulsed gas nozzle from MassSpec BV or a continuous effusive nozzle. Both of these are pumped using a 3200 l/s turbo pump. There is a skimmer mounted between the chambers to enable differentially pumping.  ​

​Liquid jet chamber

The chamber for liquid-phase studies is equipped with a liquid micro-​jet (Microliquids GmbH), and a differentially pumped time-of-flight detector can be provided. The design is based on a chamber developed by EPFL's Laboratory of Ultrafast Spectroscopy (link opens in a new window) and tested at Artemis ​[7​].​


[1] Smith, Adam D., Emily M. Warne, Darren Bellshaw, Daniel A. Horke, Maria Tudorovskya, Emma Springate, Alfred J. H. Jones, et al. ‘Mapping the Complete Reaction Path of a Complex Photochemical Reaction’. Physical Review Letters 120, no. 18 (4 May 2018): 183003. https://doi.org/10.1103/PhysRevLett.120.183003

[2] Warne, Emily M., Briony Downes-Ward, Joanne Woodhouse, Michael A. Parkes, Emma Springate, Philip A. J. Pearcy, Yu Zhang, et al. ‘Photodissociation Dynamics of Methyl Iodide Probed Using Femtosecond Extreme Ultraviolet Photoelectron Spectroscopy’. Physical Chemistry Chemical Physics 22, no. 44 (2020): 25695–703. https://doi.org/10.1039/D0CP03478A

[3] Warne, Emily M., Adam D. Smith, Daniel A. Horke, Emma Springate, Alfred J. H. Jones, Cephise Cacho, Richard T. Chapman, and Russell S. Minns. ‘Time Resolved Detection of the S(1D) Product of the UV Induced Dissociation of CS2’. The Journal of Chemical Physics 154, no. 3 (21 January 2021): 034302. https://doi.org/10.1063/5.0035045.
[4] Galinis, Gediminas, Cephise Cacho, Richard T. Chapman, Andrew M. Ellis, Marius Lewerenz, Luis G. Mendoza Luna, Russell S. Minns, et al. ‘Probing the Structure and Dynamics of Molecular Clusters Using Rotational Wave Packets’. Physical Review Letters 113, no. 4 (24 July 2014): 043004. https://doi.org/10.1103/PhysRevLett.113.043004

[5] Lee, Jason W. L., Hansjochen Köckert, David Heathcote, Divya Popat, Richard T. Chapman, Gabriel Karras, Paulina Majchrzak, Emma Springate, and Claire Vallance. ‘Three-Dimensional Covariance-Map Imaging of Molecular Structure and Dynamics on the Ultrafast Timescale’. Communications Chemistry 3, no. 1 (December 2020): 72. https://doi.org/10.1038/s42004-020-0320-3

[6] Ganjitabar, Hassan, Dhirendra P. Singh, Richard Chapman, Adrian Gardner, Russell S. Minns, Ivan Powis, Katharine L. Reid, and Arno Vredenborg. ‘The Role of the Intermediate State in Angle-Resolved Photoelectron Studies Using (2 + 1) Resonance-Enhanced Multiphoton Ionization of the Chiral Terpenes, α-Pinene and 3-Carene’. Molecular Physics 119, no. 1–2 (17 January 2021): e1808907. https://doi.org/10.1080/00268976.2020.1808907. ​

[7]   C. A. Arrell, J. Ojeda, M. Sabbar, W. A. Okell, T. Witting, T. Siegel, Z. Diveki, S. Hutchinson, L. Gallmann, U. Keller, F. van Mourik, R. T. Chapman, C. Cacho, N. Rodrigues, I. C.E. Turcu, J. W.G. Tisch, E. Springate, J. P. Marangos and M. Chergui., "A simple electron time-of-flight spectrometer for ultrafast vacuum ultraviolet photoelectron spectroscopy of liquid solutions", Rev Sci Instrum 85 103117 (2014). https://doi.org/10.1063/1.4899062

Contact: Chapman, Richard (STFC,RAL,CLF)