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Title: Robust X-ray angular correlations for the study of meso-structures

Abstract

As self-assembling nanomaterials become more sophisticated, it is becoming increasingly important to measure the structural order of finite-sized assemblies of nano-objects. These mesoscale clusters represent an acute challenge to conventional structural probes, owing to the range of implicated size scales (10 nm to several micrometres), the weak scattering signal and the dynamic nature of meso-clusters in native solution environments. The high X-ray flux and coherence of modern synchrotrons present an opportunity to extract structural information from these challenging systems, but conventional ensemble X-ray scattering averages out crucial information about local particle configurations. Conversely, a single meso-cluster scatters too weakly to recover the full diffraction pattern. Using X-ray angular cross-correlation analysis, it is possible to combine multiple noisy measurements to obtain robust structural information. This paper explores the key theoretical limits and experimental challenges that constrain the application of these methods to probing structural order in real nanomaterials. A metric is presented to quantify the signal-to-noise ratio of angular correlations, and it is used to identify several experimental artifacts that arise. In particular, it is found that background scattering, data masking and inter-cluster interference profoundly affect the quality of correlation analyses. A robust workflow is demonstrated for mitigating these effects andmore » extracting reliable angular correlations from realistic experimental data.« less

Authors:
ORCiD logo [1];  [1];  [1];  [1];  [2];  [2];  [2];  [3];  [1]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States)
  2. Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source
  3. Brookhaven National Lab. (BNL), Upton, NY (United States); Columbia Univ., New York, NY (United States)
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials (CFN)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1389241
Report Number(s):
BNL-114233-2017-JA
Journal ID: ISSN 1600-5767; JACGAR; KC0403020
Grant/Contract Number:
SC0012704
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Applied Crystallography (Online)
Additional Journal Information:
Journal Name: Journal of Applied Crystallography (Online); Journal Volume: 50; Journal Issue: 3; Journal ID: ISSN 1600-5767
Publisher:
International Union of Crystallography
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; x-ray scattering; correlation analysis; Center for Functional Nanomaterials

Citation Formats

Lhermitte, Julien R., Tian, Cheng, Stein, Aaron, Rahman, Atikur, Zhang, Yugang, Wiegart, Lutz, Fluerasu, Andrei, Gang, Oleg, and Yager, Kevin G.. Robust X-ray angular correlations for the study of meso-structures. United States: N. p., 2017. Web. doi:10.1107/S1600576717003946.
Lhermitte, Julien R., Tian, Cheng, Stein, Aaron, Rahman, Atikur, Zhang, Yugang, Wiegart, Lutz, Fluerasu, Andrei, Gang, Oleg, & Yager, Kevin G.. Robust X-ray angular correlations for the study of meso-structures. United States. doi:10.1107/S1600576717003946.
Lhermitte, Julien R., Tian, Cheng, Stein, Aaron, Rahman, Atikur, Zhang, Yugang, Wiegart, Lutz, Fluerasu, Andrei, Gang, Oleg, and Yager, Kevin G.. Mon . "Robust X-ray angular correlations for the study of meso-structures". United States. doi:10.1107/S1600576717003946. https://www.osti.gov/servlets/purl/1389241.
@article{osti_1389241,
title = {Robust X-ray angular correlations for the study of meso-structures},
author = {Lhermitte, Julien R. and Tian, Cheng and Stein, Aaron and Rahman, Atikur and Zhang, Yugang and Wiegart, Lutz and Fluerasu, Andrei and Gang, Oleg and Yager, Kevin G.},
abstractNote = {As self-assembling nanomaterials become more sophisticated, it is becoming increasingly important to measure the structural order of finite-sized assemblies of nano-objects. These mesoscale clusters represent an acute challenge to conventional structural probes, owing to the range of implicated size scales (10 nm to several micrometres), the weak scattering signal and the dynamic nature of meso-clusters in native solution environments. The high X-ray flux and coherence of modern synchrotrons present an opportunity to extract structural information from these challenging systems, but conventional ensemble X-ray scattering averages out crucial information about local particle configurations. Conversely, a single meso-cluster scatters too weakly to recover the full diffraction pattern. Using X-ray angular cross-correlation analysis, it is possible to combine multiple noisy measurements to obtain robust structural information. This paper explores the key theoretical limits and experimental challenges that constrain the application of these methods to probing structural order in real nanomaterials. A metric is presented to quantify the signal-to-noise ratio of angular correlations, and it is used to identify several experimental artifacts that arise. In particular, it is found that background scattering, data masking and inter-cluster interference profoundly affect the quality of correlation analyses. A robust workflow is demonstrated for mitigating these effects and extracting reliable angular correlations from realistic experimental data.},
doi = {10.1107/S1600576717003946},
journal = {Journal of Applied Crystallography (Online)},
number = 3,
volume = 50,
place = {United States},
year = {Mon May 08 00:00:00 EDT 2017},
month = {Mon May 08 00:00:00 EDT 2017}
}

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