Carbonic acid monohydrate
In the water-carbon dioxide system, above a pressure of 4.4 GPa, a crystalline phase consisting of an adduct of the two substances can be observed to exist in equilibrium with the aqueous fluid. The phase had been found to be triclinic, and its unit-cell parameters determined, but the full crystalli...
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ftdesyvdb:oai:bib-pubdb1.desy.de:418234 2023-05-15T15:52:30+02:00 Carbonic acid monohydrate Abramson, Evan H. Bollengier, Olivier Brown, J. Michael Journaux, Baptiste Kaminsky, Werner Pakhomova, Anna DE 2018 https://bib-pubdb1.desy.de/record/418234 https://bib-pubdb1.desy.de/search?p=id:%22PUBDB-2019-00282%22 eng eng GeoScienceWorld info:eu-repo/semantics/altIdentifier/doi/10.2138/am-2018-6554 info:eu-repo/semantics/altIdentifier/issn/1945-3027 info:eu-repo/semantics/altIdentifier/wos/WOS:000443196900009 info:eu-repo/semantics/altIdentifier/issn/0003-004X info:eu-repo/semantics/altIdentifier/doi/10.3204/PUBDB-2019-00282 https://bib-pubdb1.desy.de/record/418234 https://bib-pubdb1.desy.de/search?p=id:%22PUBDB-2019-00282%22 info:eu-repo/semantics/embargoedAccess American mineralogist 103(9), 1468 - 1472 (2018). doi:10.2138/am-2018-6554 info:eu-repo/classification/ddc/540 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2018 ftdesyvdb https://doi.org/10.2138/am-2018-6554 https://doi.org/10.3204/PUBDB-2019-00282 2022-06-30T20:19:32Z In the water-carbon dioxide system, above a pressure of 4.4 GPa, a crystalline phase consisting of an adduct of the two substances can be observed to exist in equilibrium with the aqueous fluid. The phase had been found to be triclinic, and its unit-cell parameters determined, but the full crystalline and even molecular structure remained undetermined. Here, we report new diamond-anvil cell, X-ray diffraction data of a quality sufficient to allow us to propose a full structure. The crystal exists in the P1 space group. Unit-cell parameters (at 6.5 GPa and 140 °C) are a = 5.8508(14), b = 6.557(5), c = 6.9513(6) Å, α = 88.59(2)°, β = 79.597(13)°, and $γ$ = 67.69(4)°. Direct solution for the heavy atoms (carbon and oxygen) revealed CO$_3$ units, with co-planar, but isolated, O units. Construction of a hydrogen network, in accordance with the requirements of hydrogen bonding and with minimum allowed distances between non-bonded atoms, indicates that the phase consists of a monohydrate of carbonic acid (H$_2$CO$_3$·H$_2$O) with the carbonic acid molecule in the cis-trans configuration. This is the first experimental determination of the crystalline structure of a H$_2$CO$_3$ compound. The structure serves as a guide for ab initio calculations that have until now explored only anhydrous H$_2$CO$_3$ solids, while validating calculations that indicated that high pressures should stabilize H$_2$CO$_3$ in the solid state. If 4.4 GPa is the lowest pressure at which the phase is thermodynamically stable, this probably precludes its existence in our solar system, although it may exist on larger, volatile-rich exoplanets. If, however, its range of stability extends to lower pressures at lower temperatures (which possibility has not yet been adequately explored), then it might have been be a stable form of CO$_2$ within the water-rich moons and dwarf planets prior to differentiation and might still exist on an undifferentiated Callisto. Article in Journal/Newspaper Carbonic acid DESY Publication Database (PUBDB) Anvil ENVELOPE(-64.267,-64.267,-65.239,-65.239) American Mineralogist 103 9 1468 1472 |
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Open Polar |
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DESY Publication Database (PUBDB) |
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ftdesyvdb |
language |
English |
topic |
info:eu-repo/classification/ddc/540 |
spellingShingle |
info:eu-repo/classification/ddc/540 Abramson, Evan H. Bollengier, Olivier Brown, J. Michael Journaux, Baptiste Kaminsky, Werner Pakhomova, Anna Carbonic acid monohydrate |
topic_facet |
info:eu-repo/classification/ddc/540 |
description |
In the water-carbon dioxide system, above a pressure of 4.4 GPa, a crystalline phase consisting of an adduct of the two substances can be observed to exist in equilibrium with the aqueous fluid. The phase had been found to be triclinic, and its unit-cell parameters determined, but the full crystalline and even molecular structure remained undetermined. Here, we report new diamond-anvil cell, X-ray diffraction data of a quality sufficient to allow us to propose a full structure. The crystal exists in the P1 space group. Unit-cell parameters (at 6.5 GPa and 140 °C) are a = 5.8508(14), b = 6.557(5), c = 6.9513(6) Å, α = 88.59(2)°, β = 79.597(13)°, and $γ$ = 67.69(4)°. Direct solution for the heavy atoms (carbon and oxygen) revealed CO$_3$ units, with co-planar, but isolated, O units. Construction of a hydrogen network, in accordance with the requirements of hydrogen bonding and with minimum allowed distances between non-bonded atoms, indicates that the phase consists of a monohydrate of carbonic acid (H$_2$CO$_3$·H$_2$O) with the carbonic acid molecule in the cis-trans configuration. This is the first experimental determination of the crystalline structure of a H$_2$CO$_3$ compound. The structure serves as a guide for ab initio calculations that have until now explored only anhydrous H$_2$CO$_3$ solids, while validating calculations that indicated that high pressures should stabilize H$_2$CO$_3$ in the solid state. If 4.4 GPa is the lowest pressure at which the phase is thermodynamically stable, this probably precludes its existence in our solar system, although it may exist on larger, volatile-rich exoplanets. If, however, its range of stability extends to lower pressures at lower temperatures (which possibility has not yet been adequately explored), then it might have been be a stable form of CO$_2$ within the water-rich moons and dwarf planets prior to differentiation and might still exist on an undifferentiated Callisto. |
format |
Article in Journal/Newspaper |
author |
Abramson, Evan H. Bollengier, Olivier Brown, J. Michael Journaux, Baptiste Kaminsky, Werner Pakhomova, Anna |
author_facet |
Abramson, Evan H. Bollengier, Olivier Brown, J. Michael Journaux, Baptiste Kaminsky, Werner Pakhomova, Anna |
author_sort |
Abramson, Evan H. |
title |
Carbonic acid monohydrate |
title_short |
Carbonic acid monohydrate |
title_full |
Carbonic acid monohydrate |
title_fullStr |
Carbonic acid monohydrate |
title_full_unstemmed |
Carbonic acid monohydrate |
title_sort |
carbonic acid monohydrate |
publisher |
GeoScienceWorld |
publishDate |
2018 |
url |
https://bib-pubdb1.desy.de/record/418234 https://bib-pubdb1.desy.de/search?p=id:%22PUBDB-2019-00282%22 |
op_coverage |
DE |
long_lat |
ENVELOPE(-64.267,-64.267,-65.239,-65.239) |
geographic |
Anvil |
geographic_facet |
Anvil |
genre |
Carbonic acid |
genre_facet |
Carbonic acid |
op_source |
American mineralogist 103(9), 1468 - 1472 (2018). doi:10.2138/am-2018-6554 |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.2138/am-2018-6554 info:eu-repo/semantics/altIdentifier/issn/1945-3027 info:eu-repo/semantics/altIdentifier/wos/WOS:000443196900009 info:eu-repo/semantics/altIdentifier/issn/0003-004X info:eu-repo/semantics/altIdentifier/doi/10.3204/PUBDB-2019-00282 https://bib-pubdb1.desy.de/record/418234 https://bib-pubdb1.desy.de/search?p=id:%22PUBDB-2019-00282%22 |
op_rights |
info:eu-repo/semantics/embargoedAccess |
op_doi |
https://doi.org/10.2138/am-2018-6554 https://doi.org/10.3204/PUBDB-2019-00282 |
container_title |
American Mineralogist |
container_volume |
103 |
container_issue |
9 |
container_start_page |
1468 |
op_container_end_page |
1472 |
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1766387663352365056 |