Crystal chemistry of chlormagaluminite, Mg4Al2(OH)12Cl2(H2O)2, a natural layered double hydroxide

Elena S. Zhitova, Sergey V. Krivovichev, Igor V. Pekov, Vasiliy O. Yapaskurt

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1 Citation (Scopus)

Abstract

Chlormagaluminite is the only Cl-dominated hydrotalcite-supergroup mineral species with M2+:M3+ = 2:1. The holotype sample of chlormagaluminite from the Kapaevskaya volcanic pipe (Irkutsk Oblast, Siberia, Russia) has been chemically and structurally characterized. The average chemical composition of the mineral is (electron microprobe, OH content is calculated by stoichiometry and H2O from the crystal-structure data, wt. %): MgO 33.85, FeO 1.09, Al2O3 22.07, Cl 14.72, H2Otot 30.96, Cl=O −3.39, total 99.30. The empirical formula based on Mg + Al + Fe = 6 atoms per formula unit (apfu) is [Mg3.91Fe2+ 0.07Al2.02(OH)12]Cl2.02(H2O)2.0(2). The crystal structure has been solved from single-crystal X-ray diffraction data in the space group P63/mcm, a = 5.268(3), c = 15.297(8) Å and V = 367.6(4) Å3. The refinement converged to R1 = 0.083 on the basis of 152 unique reflections with I > 2σ(I) collected at room conditions. The powder pattern contains standard reflections of a 2H polytype and two additional reflections [(010), d010 = 4.574 Å; (110), d110 = 2.647 Å] indicative of Mg and Al ordering according to the 3-√×3-√ superstructure. The structure is based upon brucite-type octahedral layers with an ordered distribution of Mg and Al over octahedral sites. The Cl anions and H2O molecules reside in the interlayer, providing a three-dimensional integrity of the structure.

Original languageEnglish
Article number221
Number of pages16
JournalMinerals
Volume9
Issue number4
DOIs
Publication statusPublished - 1 Apr 2019

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Crystal chemistry
crystal chemistry
crystal structure
hydroxide
hydrotalcite
brucite
mineral
Minerals
stoichiometry
Crystal structure
electron probe analysis
anion
pipe
chemical composition
X-ray diffraction
crystal
Stoichiometry
Negative ions
Pipe
Single crystals

Scopus subject areas

  • Geotechnical Engineering and Engineering Geology
  • Geology

Cite this

@article{0abbe3407ebe4ef6a4a8bbb0e77edc54,
title = "Crystal chemistry of chlormagaluminite, Mg4Al2(OH)12Cl2(H2O)2, a natural layered double hydroxide",
abstract = "Chlormagaluminite is the only Cl-dominated hydrotalcite-supergroup mineral species with M2+:M3+ = 2:1. The holotype sample of chlormagaluminite from the Kapaevskaya volcanic pipe (Irkutsk Oblast, Siberia, Russia) has been chemically and structurally characterized. The average chemical composition of the mineral is (electron microprobe, OH content is calculated by stoichiometry and H2O from the crystal-structure data, wt. {\%}): MgO 33.85, FeO 1.09, Al2O3 22.07, Cl 14.72, H2Otot 30.96, Cl=O −3.39, total 99.30. The empirical formula based on Mg + Al + Fe = 6 atoms per formula unit (apfu) is [Mg3.91Fe2+ 0.07Al2.02(OH)12]Cl2.02(H2O)2.0(2). The crystal structure has been solved from single-crystal X-ray diffraction data in the space group P63/mcm, a = 5.268(3), c = 15.297(8) {\AA} and V = 367.6(4) {\AA}3. The refinement converged to R1 = 0.083 on the basis of 152 unique reflections with I > 2σ(I) collected at room conditions. The powder pattern contains standard reflections of a 2H polytype and two additional reflections [(010), d010 = 4.574 {\AA}; (110), d110 = 2.647 {\AA}] indicative of Mg and Al ordering according to the 3-√×3-√ superstructure. The structure is based upon brucite-type octahedral layers with an ordered distribution of Mg and Al over octahedral sites. The Cl− anions and H2O molecules reside in the interlayer, providing a three-dimensional integrity of the structure.",
keywords = "Chlormagaluminite, Hydrotalcite supergroup, Layered double hydroxide, LDH, Quintinite group, Structure",
author = "Zhitova, {Elena S.} and Krivovichev, {Sergey V.} and Pekov, {Igor V.} and Yapaskurt, {Vasiliy O.}",
year = "2019",
month = "4",
day = "1",
doi = "10.3390/min9040221",
language = "English",
volume = "9",
journal = "Minerals",
issn = "2075-163X",
publisher = "MDPI AG",
number = "4",

}

Crystal chemistry of chlormagaluminite, Mg4Al2(OH)12Cl2(H2O)2, a natural layered double hydroxide. / Zhitova, Elena S.; Krivovichev, Sergey V.; Pekov, Igor V.; Yapaskurt, Vasiliy O.

In: Minerals, Vol. 9, No. 4, 221, 01.04.2019.

Research outputpeer-review

TY - JOUR

T1 - Crystal chemistry of chlormagaluminite, Mg4Al2(OH)12Cl2(H2O)2, a natural layered double hydroxide

AU - Zhitova, Elena S.

AU - Krivovichev, Sergey V.

AU - Pekov, Igor V.

AU - Yapaskurt, Vasiliy O.

PY - 2019/4/1

Y1 - 2019/4/1

N2 - Chlormagaluminite is the only Cl-dominated hydrotalcite-supergroup mineral species with M2+:M3+ = 2:1. The holotype sample of chlormagaluminite from the Kapaevskaya volcanic pipe (Irkutsk Oblast, Siberia, Russia) has been chemically and structurally characterized. The average chemical composition of the mineral is (electron microprobe, OH content is calculated by stoichiometry and H2O from the crystal-structure data, wt. %): MgO 33.85, FeO 1.09, Al2O3 22.07, Cl 14.72, H2Otot 30.96, Cl=O −3.39, total 99.30. The empirical formula based on Mg + Al + Fe = 6 atoms per formula unit (apfu) is [Mg3.91Fe2+ 0.07Al2.02(OH)12]Cl2.02(H2O)2.0(2). The crystal structure has been solved from single-crystal X-ray diffraction data in the space group P63/mcm, a = 5.268(3), c = 15.297(8) Å and V = 367.6(4) Å3. The refinement converged to R1 = 0.083 on the basis of 152 unique reflections with I > 2σ(I) collected at room conditions. The powder pattern contains standard reflections of a 2H polytype and two additional reflections [(010), d010 = 4.574 Å; (110), d110 = 2.647 Å] indicative of Mg and Al ordering according to the 3-√×3-√ superstructure. The structure is based upon brucite-type octahedral layers with an ordered distribution of Mg and Al over octahedral sites. The Cl− anions and H2O molecules reside in the interlayer, providing a three-dimensional integrity of the structure.

AB - Chlormagaluminite is the only Cl-dominated hydrotalcite-supergroup mineral species with M2+:M3+ = 2:1. The holotype sample of chlormagaluminite from the Kapaevskaya volcanic pipe (Irkutsk Oblast, Siberia, Russia) has been chemically and structurally characterized. The average chemical composition of the mineral is (electron microprobe, OH content is calculated by stoichiometry and H2O from the crystal-structure data, wt. %): MgO 33.85, FeO 1.09, Al2O3 22.07, Cl 14.72, H2Otot 30.96, Cl=O −3.39, total 99.30. The empirical formula based on Mg + Al + Fe = 6 atoms per formula unit (apfu) is [Mg3.91Fe2+ 0.07Al2.02(OH)12]Cl2.02(H2O)2.0(2). The crystal structure has been solved from single-crystal X-ray diffraction data in the space group P63/mcm, a = 5.268(3), c = 15.297(8) Å and V = 367.6(4) Å3. The refinement converged to R1 = 0.083 on the basis of 152 unique reflections with I > 2σ(I) collected at room conditions. The powder pattern contains standard reflections of a 2H polytype and two additional reflections [(010), d010 = 4.574 Å; (110), d110 = 2.647 Å] indicative of Mg and Al ordering according to the 3-√×3-√ superstructure. The structure is based upon brucite-type octahedral layers with an ordered distribution of Mg and Al over octahedral sites. The Cl− anions and H2O molecules reside in the interlayer, providing a three-dimensional integrity of the structure.

KW - Chlormagaluminite

KW - Hydrotalcite supergroup

KW - Layered double hydroxide

KW - LDH

KW - Quintinite group

KW - Structure

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UR - http://www.mendeley.com/research/crystal-chemistry-chlormagaluminite-mg4al2oh12cl2h2o2-natural-layered-double-hydroxide

U2 - 10.3390/min9040221

DO - 10.3390/min9040221

M3 - Article

VL - 9

JO - Minerals

JF - Minerals

SN - 2075-163X

IS - 4

M1 - 221

ER -