TY - JOUR
T1 - Revealing the structures and relationships of Ca(ii)-Fe(iii)-AsO4minerals
T2 - arseniosiderite and yukonite
AU - King, Graham
AU - Celikin, Mert
AU - Gomez, Mario Alberto
AU - Becze, Levente
AU - Petkov, Valeri
AU - Della Ventura, Giancarlo
N1 - Funding Information:
We would like to thank Robin Hansen and Mike Rumsey, Curators of Minerals at the Natural History Museum London for the donation of the original natural Tagish Lake Yukonite sample and Romanech arseniosiderite. We also kindly thank Professor Gennaro Ventruti from the Universita di Bari Aldo Moro for help in obtaining the Italian yukonite samples and Professor George Demopoulos at McGill University for previous guidance and financial support of this research. Matthew Bohan from McGill University is also thanked for useful discussions. MAG kindly thanks Prof. Yongfeng Jia and the National Key R&D Program of China (no. 2017 YFD 0800301) for support. MAG also thanks the National Natural Science Foundation of China (no. 41703129) for financial support. GDV was supported by a grant to the Department of Science, Roma Tre University (MIUR-Italy Dipartimenti di Eccellenza, ARTICOLO 1, COMMI 314 – 337 LEGGE 232/ 2016). Part of the research described in this paper was performed at the Canadian Light Source, a national research facility of the University of Saskatchewan, which is supported by the Canada Foundation for Innovation (CFI), the Natural Sciences and Engineering Research Council (NSERC), the National Research Council (NRC), the Canadian Institutes of Health Research (CIHR), the Government of Saskatchewan, and the University of Saskatchewan. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357.
Publisher Copyright:
© 2020 The Royal Society of Chemistry.
PY - 2020/12
Y1 - 2020/12
N2 - The low crystallinity of arsenic (As) containing minerals such as arseniosiderite and yukonite has made a detailed understanding of their atomic structures elusive. X-ray pair distribution function (PDF) and transmission electron microscopy (TEM) were used to gain a detailed understanding of the short and medium-range structural features. High-resolution synchrotron powder diffraction data showed long-range order in arseniosiderite occurs along one direction. PDF data confirmed arseniosiderite has the same general structure as robertsite and mitridatite but with the layers occasionally shifted to disrupt long-range order. Use of small box and reverse Monte Carlo modeling of the PDF data gave the first complete set of atomic coordinates for arseniosiderite. TEM confirmed the degree of interlayer order is generally high. PDF and TEM data show that yukonite is a nano-sized analog of arseniosiderite which lacks any long-range order but is locally similar. The structural evolution of arseniosiderite from yukonite was observed for the first time in a natural specimen via TEM. PDF data on several yukonite samples reveal rather sudden drops in the degree of structural correlation as a function of distance. These drops occur from yukonite being composed of small layers made of integer numbers of large nonamers of edge-sharing FeO6 octahedra, as seen in arseniosiderite. However, these layers are 2 or 3 nonamers in width, with little structural correlation between layers. Thus our work provides a more complete nano/microscopic picture of the key structural features in these minerals found in mining ores and wastes around the world.
AB - The low crystallinity of arsenic (As) containing minerals such as arseniosiderite and yukonite has made a detailed understanding of their atomic structures elusive. X-ray pair distribution function (PDF) and transmission electron microscopy (TEM) were used to gain a detailed understanding of the short and medium-range structural features. High-resolution synchrotron powder diffraction data showed long-range order in arseniosiderite occurs along one direction. PDF data confirmed arseniosiderite has the same general structure as robertsite and mitridatite but with the layers occasionally shifted to disrupt long-range order. Use of small box and reverse Monte Carlo modeling of the PDF data gave the first complete set of atomic coordinates for arseniosiderite. TEM confirmed the degree of interlayer order is generally high. PDF and TEM data show that yukonite is a nano-sized analog of arseniosiderite which lacks any long-range order but is locally similar. The structural evolution of arseniosiderite from yukonite was observed for the first time in a natural specimen via TEM. PDF data on several yukonite samples reveal rather sudden drops in the degree of structural correlation as a function of distance. These drops occur from yukonite being composed of small layers made of integer numbers of large nonamers of edge-sharing FeO6 octahedra, as seen in arseniosiderite. However, these layers are 2 or 3 nonamers in width, with little structural correlation between layers. Thus our work provides a more complete nano/microscopic picture of the key structural features in these minerals found in mining ores and wastes around the world.
UR - http://www.scopus.com/inward/record.url?scp=85098458249&partnerID=8YFLogxK
U2 - 10.1039/d0en00503g
DO - 10.1039/d0en00503g
M3 - Article
AN - SCOPUS:85098458249
VL - 7
SP - 3735
EP - 3745
JO - Environmental Science: Nano
JF - Environmental Science: Nano
SN - 2051-8153
IS - 12
ER -