CRYSTAL CHEMISTRY AND SURFACE CONFIGURATIONS OF TWO IRON-BEARING TRIOCTAHEDRAL MICA-1M POLYTYPES
The aim of this paper is to explore the crystal chemical features of both the bulk and the uppermost surface layers of two trioctahedral Fe-rich mica-1M (space group C2/m) polytypes: a tetra-ferriphlogopite from an alkali-carbonatic complex near Tapira (Belo Horizonte, Minas Gerals, Brazil) and a Fe...
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Online Access: | http://hdl.handle.net/11380/1060114 https://doi.org/10.1346/CCMN.2014.0620401 |
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ftunivmodena:oai:iris.unimore.it:11380/1060114 2024-04-14T08:14:28+00:00 CRYSTAL CHEMISTRY AND SURFACE CONFIGURATIONS OF TWO IRON-BEARING TRIOCTAHEDRAL MICA-1M POLYTYPES ELMI, Chiara BRIGATTI, Maria Franca PASQUALI, Luca MONTECCHI, Monica NANNARONE, Stefano Guggenheim, S. Elmi, Chiara Brigatti, Maria Franca Guggenheim, S. Pasquali, Luca Montecchi, Monica Nannarone, Stefano 2014 STAMPA http://hdl.handle.net/11380/1060114 https://doi.org/10.1346/CCMN.2014.0620401 eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000346817200008 volume:62 firstpage:243 lastpage:252 journal:CLAYS AND CLAY MINERALS http://hdl.handle.net/11380/1060114 doi:10.1346/CCMN.2014.0620401 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-84908181780 info:eu-repo/semantics/closedAccess crystal chemistry crystal structure surface iron-bearing trioctahedral mica-1M polytypes info:eu-repo/semantics/article 2014 ftunivmodena https://doi.org/10.1346/CCMN.2014.0620401 2024-03-21T17:36:55Z The aim of this paper is to explore the crystal chemical features of both the bulk and the uppermost surface layers of two trioctahedral Fe-rich mica-1M (space group C2/m) polytypes: a tetra-ferriphlogopite from an alkali-carbonatic complex near Tapira (Belo Horizonte, Minas Gerals, Brazil) and a Fe2+-bearing phlogopite also containing Fe3+ in tetrahedral sites from the Kovdor carbonatite-bearing alkaline-ultrabasic complex (Kola Peninsula, Russia). The chemical formulae are [XII](K0.99) [VI](Fe2+0.08 Fe3+0.15 Mg2.76 Ti0.01) [IV](Fe3+0.82 Si3.18) O10.37 (F0.24 OH1.39) and [XII](K0.94 Na0.06) [VI](Fe2+0.17 Fe3+0.05 Mg2.75 Mn0.01 Ti0.05) [IV](Fe3+0.16 Al0.84 Si3.00) O10.21 (F0.35 OH1.44) for tetra-ferriphlogopite and Fe-bearing phlogopite, respectively. The two minerals show a pronounced difference in tetrahedral composition, where Fe for Si substitution is at 20.5% in tetra-ferriphlogopite and at 4% in Fe-bearing phlogopite. Fe3+ substitution produces an increase of the tetrahedral sheet thickness and of mean tetrahedral edge lengths in tetra-ferriphlogopite with respect to Fe-bearing phlogopite. The tetrahedral rotation angle (α) changes remarkably from tetra-ferriphlogopite (α = 10.5°) to the Fe-bearing phlogopite (α = 8.5°), thus indicating a significantly greater tetrahedral ring distortion in the tetra-ferriphlogopite with respect to the Fe-bearing phlogopite. The interconnection between α and tetrahedral flattening angle () may indirectly suggest the variation of due to Fe for Si tetrahedral substitution. Crystal chemical modifications at the mineral surface were investigated via X-ray Photoelectron Spectroscopy by comparing data related to the surface to data originating from the bulk. The local population at the anionic position can be obtained by considering that the binding energy of photoelectron peaks is dependent on the chemical state of atoms and their local environment. If oxygen is substituted by fluorine, the binding energy of Mg was observed to shift to higher values. By considering the Mg1s ... Article in Journal/Newspaper kola peninsula Archivio della ricerca dell'Università di Modena e Reggio Emilia (Unimore: IRIS) Kola Peninsula Kovdor ENVELOPE(30.620,30.620,67.534,67.534) Clays and Clay Minerals 62 4 243 252 |
institution |
Open Polar |
collection |
Archivio della ricerca dell'Università di Modena e Reggio Emilia (Unimore: IRIS) |
op_collection_id |
ftunivmodena |
language |
English |
topic |
crystal chemistry crystal structure surface iron-bearing trioctahedral mica-1M polytypes |
spellingShingle |
crystal chemistry crystal structure surface iron-bearing trioctahedral mica-1M polytypes ELMI, Chiara BRIGATTI, Maria Franca PASQUALI, Luca MONTECCHI, Monica NANNARONE, Stefano Guggenheim, S. CRYSTAL CHEMISTRY AND SURFACE CONFIGURATIONS OF TWO IRON-BEARING TRIOCTAHEDRAL MICA-1M POLYTYPES |
topic_facet |
crystal chemistry crystal structure surface iron-bearing trioctahedral mica-1M polytypes |
description |
The aim of this paper is to explore the crystal chemical features of both the bulk and the uppermost surface layers of two trioctahedral Fe-rich mica-1M (space group C2/m) polytypes: a tetra-ferriphlogopite from an alkali-carbonatic complex near Tapira (Belo Horizonte, Minas Gerals, Brazil) and a Fe2+-bearing phlogopite also containing Fe3+ in tetrahedral sites from the Kovdor carbonatite-bearing alkaline-ultrabasic complex (Kola Peninsula, Russia). The chemical formulae are [XII](K0.99) [VI](Fe2+0.08 Fe3+0.15 Mg2.76 Ti0.01) [IV](Fe3+0.82 Si3.18) O10.37 (F0.24 OH1.39) and [XII](K0.94 Na0.06) [VI](Fe2+0.17 Fe3+0.05 Mg2.75 Mn0.01 Ti0.05) [IV](Fe3+0.16 Al0.84 Si3.00) O10.21 (F0.35 OH1.44) for tetra-ferriphlogopite and Fe-bearing phlogopite, respectively. The two minerals show a pronounced difference in tetrahedral composition, where Fe for Si substitution is at 20.5% in tetra-ferriphlogopite and at 4% in Fe-bearing phlogopite. Fe3+ substitution produces an increase of the tetrahedral sheet thickness and of mean tetrahedral edge lengths in tetra-ferriphlogopite with respect to Fe-bearing phlogopite. The tetrahedral rotation angle (α) changes remarkably from tetra-ferriphlogopite (α = 10.5°) to the Fe-bearing phlogopite (α = 8.5°), thus indicating a significantly greater tetrahedral ring distortion in the tetra-ferriphlogopite with respect to the Fe-bearing phlogopite. The interconnection between α and tetrahedral flattening angle () may indirectly suggest the variation of due to Fe for Si tetrahedral substitution. Crystal chemical modifications at the mineral surface were investigated via X-ray Photoelectron Spectroscopy by comparing data related to the surface to data originating from the bulk. The local population at the anionic position can be obtained by considering that the binding energy of photoelectron peaks is dependent on the chemical state of atoms and their local environment. If oxygen is substituted by fluorine, the binding energy of Mg was observed to shift to higher values. By considering the Mg1s ... |
author2 |
Elmi, Chiara Brigatti, Maria Franca Guggenheim, S. Pasquali, Luca Montecchi, Monica Nannarone, Stefano |
format |
Article in Journal/Newspaper |
author |
ELMI, Chiara BRIGATTI, Maria Franca PASQUALI, Luca MONTECCHI, Monica NANNARONE, Stefano Guggenheim, S. |
author_facet |
ELMI, Chiara BRIGATTI, Maria Franca PASQUALI, Luca MONTECCHI, Monica NANNARONE, Stefano Guggenheim, S. |
author_sort |
ELMI, Chiara |
title |
CRYSTAL CHEMISTRY AND SURFACE CONFIGURATIONS OF TWO IRON-BEARING TRIOCTAHEDRAL MICA-1M POLYTYPES |
title_short |
CRYSTAL CHEMISTRY AND SURFACE CONFIGURATIONS OF TWO IRON-BEARING TRIOCTAHEDRAL MICA-1M POLYTYPES |
title_full |
CRYSTAL CHEMISTRY AND SURFACE CONFIGURATIONS OF TWO IRON-BEARING TRIOCTAHEDRAL MICA-1M POLYTYPES |
title_fullStr |
CRYSTAL CHEMISTRY AND SURFACE CONFIGURATIONS OF TWO IRON-BEARING TRIOCTAHEDRAL MICA-1M POLYTYPES |
title_full_unstemmed |
CRYSTAL CHEMISTRY AND SURFACE CONFIGURATIONS OF TWO IRON-BEARING TRIOCTAHEDRAL MICA-1M POLYTYPES |
title_sort |
crystal chemistry and surface configurations of two iron-bearing trioctahedral mica-1m polytypes |
publishDate |
2014 |
url |
http://hdl.handle.net/11380/1060114 https://doi.org/10.1346/CCMN.2014.0620401 |
long_lat |
ENVELOPE(30.620,30.620,67.534,67.534) |
geographic |
Kola Peninsula Kovdor |
geographic_facet |
Kola Peninsula Kovdor |
genre |
kola peninsula |
genre_facet |
kola peninsula |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000346817200008 volume:62 firstpage:243 lastpage:252 journal:CLAYS AND CLAY MINERALS http://hdl.handle.net/11380/1060114 doi:10.1346/CCMN.2014.0620401 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-84908181780 |
op_rights |
info:eu-repo/semantics/closedAccess |
op_doi |
https://doi.org/10.1346/CCMN.2014.0620401 |
container_title |
Clays and Clay Minerals |
container_volume |
62 |
container_issue |
4 |
container_start_page |
243 |
op_container_end_page |
252 |
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1796312653064306688 |