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Title: Novel technique for spatially resolved imaging of molecular bond orientations using x-ray birefringence

Abstract

Birefringence has been observed in anisotropic materials transmitting linearly polarized X-ray beams tuned close to an absorption edge of a specific element in the material. Synchrotron bending magnets provide X-ray beams of sufficiently high brightness and cross section for spatially resolved measurements of birefringence. The recently developed X-ray Birefringence Imaging (XBI) technique has been successfully applied for the first time using the versatile test beamline B16 at Diamond Light Source. Orientational distributions of the C–Br bonds of brominated “guest” molecules within crystalline “host” tunnel structures (in thiourea or urea inclusion compounds) have been studied using linearly polarized incident X-rays near the Br K-edge. Imaging of domain structures, changes in C–Br bond orientations associated with order-disorder phase transitions, and the effects of dynamic averaging of C–Br bond orientations have been demonstrated. The XBI setup uses a vertically deflecting high-resolution double-crystal monochromator upstream from the sample and a horizontally deflecting single-crystal polarization analyzer downstream, with a Bragg angle as close as possible to 45°. In this way, the ellipticity and rotation angle of the polarization of the beam transmitted through the sample is measured as in polarizing optical microscopy. The theoretical instrumental background calculated from the elliptical polarization of the bending-magnet X-rays,more » the imperfect polarization discrimination of the analyzer, and the correlation between vertical position and photon energy introduced by the monochromator agrees well with experimental observations. The background is calculated analytically because the region of X-ray phase space selected by this setup is sampled inefficiently by standard methods.« less

Authors:
; ;  [1]; ; ;  [2];  [3]
  1. Diamond Light Source Ltd, Harwell Science and Innovation Campus, Chilton, Didcot, Oxfordshire OX11 0DE (United Kingdom)
  2. School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT (United Kingdom)
  3. Department of Structural Biology, Weizmann Institute of Science, 234 Herzl St., Rehovot 7610001 (Israel)
Publication Date:
OSTI Identifier:
22608435
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1741; Journal Issue: 1; Conference: SRI2015: 12. international conference on synchrotron radiation instrumentation, New York, NY (United States), 6-10 Jul 2015; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABSORPTION; ANISOTROPY; BIREFRINGENCE; BORON; BRAGG REFLECTION; CARBON; CLATHRATES; CROSS SECTIONS; DIAMONDS; DOMAIN STRUCTURE; MAGNETS; MONOCHROMATORS; MONOCRYSTALS; OPTICAL MICROSCOPY; ORDER-DISORDER TRANSFORMATIONS; PHASE SPACE; POLARIZATION; RESOLUTION; SYNCHROTRONS; X RADIATION

Citation Formats

Sutter, John P., E-mail: john.sutter@diamond.ac.uk, Dolbnya, Igor P., Collins, Stephen P., Harris, Kenneth D. M., E-mail: HarrisKDM@cardiff.ac.uk, Edwards-Gau, Gregory R., Kariuki, Benson M., and Palmer, Benjamin A.. Novel technique for spatially resolved imaging of molecular bond orientations using x-ray birefringence. United States: N. p., 2016. Web. doi:10.1063/1.4952929.
Sutter, John P., E-mail: john.sutter@diamond.ac.uk, Dolbnya, Igor P., Collins, Stephen P., Harris, Kenneth D. M., E-mail: HarrisKDM@cardiff.ac.uk, Edwards-Gau, Gregory R., Kariuki, Benson M., & Palmer, Benjamin A.. Novel technique for spatially resolved imaging of molecular bond orientations using x-ray birefringence. United States. doi:10.1063/1.4952929.
Sutter, John P., E-mail: john.sutter@diamond.ac.uk, Dolbnya, Igor P., Collins, Stephen P., Harris, Kenneth D. M., E-mail: HarrisKDM@cardiff.ac.uk, Edwards-Gau, Gregory R., Kariuki, Benson M., and Palmer, Benjamin A.. 2016. "Novel technique for spatially resolved imaging of molecular bond orientations using x-ray birefringence". United States. doi:10.1063/1.4952929.
@article{osti_22608435,
title = {Novel technique for spatially resolved imaging of molecular bond orientations using x-ray birefringence},
author = {Sutter, John P., E-mail: john.sutter@diamond.ac.uk and Dolbnya, Igor P. and Collins, Stephen P. and Harris, Kenneth D. M., E-mail: HarrisKDM@cardiff.ac.uk and Edwards-Gau, Gregory R. and Kariuki, Benson M. and Palmer, Benjamin A.},
abstractNote = {Birefringence has been observed in anisotropic materials transmitting linearly polarized X-ray beams tuned close to an absorption edge of a specific element in the material. Synchrotron bending magnets provide X-ray beams of sufficiently high brightness and cross section for spatially resolved measurements of birefringence. The recently developed X-ray Birefringence Imaging (XBI) technique has been successfully applied for the first time using the versatile test beamline B16 at Diamond Light Source. Orientational distributions of the C–Br bonds of brominated “guest” molecules within crystalline “host” tunnel structures (in thiourea or urea inclusion compounds) have been studied using linearly polarized incident X-rays near the Br K-edge. Imaging of domain structures, changes in C–Br bond orientations associated with order-disorder phase transitions, and the effects of dynamic averaging of C–Br bond orientations have been demonstrated. The XBI setup uses a vertically deflecting high-resolution double-crystal monochromator upstream from the sample and a horizontally deflecting single-crystal polarization analyzer downstream, with a Bragg angle as close as possible to 45°. In this way, the ellipticity and rotation angle of the polarization of the beam transmitted through the sample is measured as in polarizing optical microscopy. The theoretical instrumental background calculated from the elliptical polarization of the bending-magnet X-rays, the imperfect polarization discrimination of the analyzer, and the correlation between vertical position and photon energy introduced by the monochromator agrees well with experimental observations. The background is calculated analytically because the region of X-ray phase space selected by this setup is sampled inefficiently by standard methods.},
doi = {10.1063/1.4952929},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1741,
place = {United States},
year = 2016,
month = 7
}
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