DL Template

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Soft X-ray Science
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Introduction

• Soft X-ray 1eV ? few kV.
• Strong overlap with particles science case.
  Provides complementary information.
• Covers a very broad science range archaeology ?
  At. Mol. ? magnetic materials ? lasers.

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X-ray adsorption

• EXAFS/NEXAFS very common at SRS.
• 1D scan (i.e. counts vs energy).
• Adapted to suite sample and/or science.

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XAS Catalysis

• Objectives are to study chemical reactions at
  surfaces.
• Growing realisation that in situ measurements are
  required.
• High gas pressure requires short path lengths for
  soft X-rays.
• Detectors not currently designed for these
  measurements/ tricky to set up.

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XAS Catalysis
Marsh et al JCP,B108, 605 (2004)
Todd et al Geochim. Cosmochim., 67, 2137 (2003)
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XAS Catalysis

• Requirements (short / medium term)
• Robust i.e. can withstand baking.
• Sample at approx 1 atm gas pressure.
• Isolated from chamber by window.
• Small detector that can be placed close to sample.

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XAS Catalysis

• Long term requirements are to study both
  structure and dynamical properties
• High count rates.
• Good energy resolution.
• Fs resolution with pulsed source.
• Spatial resolution nms.

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XAS soft condensed matter

• Includes surface properties of polymers, drugs
  and biomaterials.
• high pressure required due to low vapour
  pressure or change in structure under wet/dry
  conditions.
• Radiation damage.
• Problems similar to catalysis.

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XAS soft condensed matter

• Future work requires
• Environmental/processing conditions
• And/or
• Imaging (e.g. soft x-ray scanning transmission
  microscopy).

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XAS soft condensed matterKilcoyne et al. J.
Sync. Rad., 10,125 (2003)
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XAS soft condensed matter
3T3 Fibroblast (Denbeaux et al NIM, A467, 841
(2001)
Uesugi et al NIM, A467, 853 (2001).
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XAS SEXAFS

• Surface extended X-ray adsorption fine structure.
  
• Structure of surfaces and inorganic/organic
  layers on model surfaces.
• Also use photoelectron spectroscopy.

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XAS SEXAFS

• Future directions
• Model surfaces to higher pressure.
• Energy dispersive X-ray fluorescence detector?
• High count rates.

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XAS Magnetic materials
Bateman et al, NIM, A467, 1140 (2001).

• Magnetic Storage devices
• Advantages over TEY not influenced by complex
  magnetic fields.
• Self adsorption influence LII/LIII ratio.

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XAS Magnetic materials

• STXM magnetic domains in addition to XMCD
  spectra.
• Must be linearly proportional to absorption.

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Resonant Inelastic X-ray Scattering

• Probe the electronic structure of
• Solid state materials ? band structure.
• Adsorbates on surfaces.
• Gas phase.
• Liquid samples.
• Soft X-ray Emission Magnetic Circular Dichroism.

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Resonant Inelastic X-ray Scattering
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Resonant Inelastic X-ray Scattering
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Resonant Inelastic X-ray Scattering
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