High-pressure synthetic (Na 0.97Mg 0.03)(Mg 0.43Fe 0.17 3+Si 0.40)Si 2O 6, with six-coordinated silicon, isostructural with P2/n omphacite

Esther S. Posner, Jürgen Konzett, Daniel J. Frost, Robert T Downs, Hexiong Yang

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The title compound, (sodium magnesium) [magnesium iron(III) silicon] disilicate, Na 0.97Mg 0.03)(Mg 0.43Fe 0.17 3+Si 0.40)Si 2O 6, is isotypic with ordered P2/n omphacite. Its structure is characterized by single chains of corner-sharing SiO 4 tetra-hedra, extending along the c axis, which are crosslinked by bands of edge-sharing octa-hedra (site symmetry 2), statistically occupied by (Mg 2+ + Fe 3+ + Si 4+). Between the bands built up of the octahedra are two non-equivalent highly distorted six-coordinated sites (site symmetry 2), statistically occupied by (Na + Mg). In contrast to omphacites, the great differences in size and charge between Mg 2+ and Si 4+ result in complete, rather than partial, ordering of Mg and Si into two distinct octa-hedral sites, whereas Fe 3+ is disordered between the two sites. The octa-hedron filled by (Mg + Fe) is larger and markedly more distorted than that occupied by (Si + Fe). The average (Mg + Fe) - O and ( VISi + Fe) - O bond lengths are 2.075 and 1.850 Å, respectively.

Original languageEnglish (US)
JournalActa Crystallographica Section E: Structure Reports Online
Volume68
Issue number2
DOIs
StatePublished - Feb 2012

Fingerprint

Silicon
Magnesium
magnesium
Sodium Compounds
Sodium compounds
sodium compounds
Bond length
symmetry
silicon
Iron
iron

Keywords

  • data-to-parameter ratio = 15.4
  • disorder in main residue
  • mean σ(Si-O) = 0.002 Å
  • R factor = 0.036
  • single-crystal X-ray study
  • T = 293 K
  • wR factor = 0.085

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Materials Science(all)
  • Chemistry(all)

Cite this

High-pressure synthetic (Na 0.97Mg 0.03)(Mg 0.43Fe 0.17 3+Si 0.40)Si 2O 6, with six-coordinated silicon, isostructural with P2/n omphacite. / Posner, Esther S.; Konzett, Jürgen; Frost, Daniel J.; Downs, Robert T; Yang, Hexiong.

In: Acta Crystallographica Section E: Structure Reports Online, Vol. 68, No. 2, 02.2012.

Research output: Contribution to journalArticle

@article{5b4f210b3a8c43d5aa8c206116491db7,
title = "High-pressure synthetic (Na 0.97Mg 0.03)(Mg 0.43Fe 0.17 3+Si 0.40)Si 2O 6, with six-coordinated silicon, isostructural with P2/n omphacite",
abstract = "The title compound, (sodium magnesium) [magnesium iron(III) silicon] disilicate, Na 0.97Mg 0.03)(Mg 0.43Fe 0.17 3+Si 0.40)Si 2O 6, is isotypic with ordered P2/n omphacite. Its structure is characterized by single chains of corner-sharing SiO 4 tetra-hedra, extending along the c axis, which are crosslinked by bands of edge-sharing octa-hedra (site symmetry 2), statistically occupied by (Mg 2+ + Fe 3+ + Si 4+). Between the bands built up of the octahedra are two non-equivalent highly distorted six-coordinated sites (site symmetry 2), statistically occupied by (Na + Mg). In contrast to omphacites, the great differences in size and charge between Mg 2+ and Si 4+ result in complete, rather than partial, ordering of Mg and Si into two distinct octa-hedral sites, whereas Fe 3+ is disordered between the two sites. The octa-hedron filled by (Mg + Fe) is larger and markedly more distorted than that occupied by (Si + Fe). The average (Mg + Fe) - O and ( VISi + Fe) - O bond lengths are 2.075 and 1.850 {\AA}, respectively.",
keywords = "data-to-parameter ratio = 15.4, disorder in main residue, mean σ(Si-O) = 0.002 {\AA}, R factor = 0.036, single-crystal X-ray study, T = 293 K, wR factor = 0.085",
author = "Posner, {Esther S.} and J{\"u}rgen Konzett and Frost, {Daniel J.} and Downs, {Robert T} and Hexiong Yang",
year = "2012",
month = "2",
doi = "10.1107/S1600536812002966",
language = "English (US)",
volume = "68",
journal = "Acta Crystallographica Section E: Structure Reports Online",
issn = "1600-5368",
publisher = "International Union of Crystallography",
number = "2",

}

TY - JOUR

T1 - High-pressure synthetic (Na 0.97Mg 0.03)(Mg 0.43Fe 0.17 3+Si 0.40)Si 2O 6, with six-coordinated silicon, isostructural with P2/n omphacite

AU - Posner, Esther S.

AU - Konzett, Jürgen

AU - Frost, Daniel J.

AU - Downs, Robert T

AU - Yang, Hexiong

PY - 2012/2

Y1 - 2012/2

N2 - The title compound, (sodium magnesium) [magnesium iron(III) silicon] disilicate, Na 0.97Mg 0.03)(Mg 0.43Fe 0.17 3+Si 0.40)Si 2O 6, is isotypic with ordered P2/n omphacite. Its structure is characterized by single chains of corner-sharing SiO 4 tetra-hedra, extending along the c axis, which are crosslinked by bands of edge-sharing octa-hedra (site symmetry 2), statistically occupied by (Mg 2+ + Fe 3+ + Si 4+). Between the bands built up of the octahedra are two non-equivalent highly distorted six-coordinated sites (site symmetry 2), statistically occupied by (Na + Mg). In contrast to omphacites, the great differences in size and charge between Mg 2+ and Si 4+ result in complete, rather than partial, ordering of Mg and Si into two distinct octa-hedral sites, whereas Fe 3+ is disordered between the two sites. The octa-hedron filled by (Mg + Fe) is larger and markedly more distorted than that occupied by (Si + Fe). The average (Mg + Fe) - O and ( VISi + Fe) - O bond lengths are 2.075 and 1.850 Å, respectively.

AB - The title compound, (sodium magnesium) [magnesium iron(III) silicon] disilicate, Na 0.97Mg 0.03)(Mg 0.43Fe 0.17 3+Si 0.40)Si 2O 6, is isotypic with ordered P2/n omphacite. Its structure is characterized by single chains of corner-sharing SiO 4 tetra-hedra, extending along the c axis, which are crosslinked by bands of edge-sharing octa-hedra (site symmetry 2), statistically occupied by (Mg 2+ + Fe 3+ + Si 4+). Between the bands built up of the octahedra are two non-equivalent highly distorted six-coordinated sites (site symmetry 2), statistically occupied by (Na + Mg). In contrast to omphacites, the great differences in size and charge between Mg 2+ and Si 4+ result in complete, rather than partial, ordering of Mg and Si into two distinct octa-hedral sites, whereas Fe 3+ is disordered between the two sites. The octa-hedron filled by (Mg + Fe) is larger and markedly more distorted than that occupied by (Si + Fe). The average (Mg + Fe) - O and ( VISi + Fe) - O bond lengths are 2.075 and 1.850 Å, respectively.

KW - data-to-parameter ratio = 15.4

KW - disorder in main residue

KW - mean σ(Si-O) = 0.002 Å

KW - R factor = 0.036

KW - single-crystal X-ray study

KW - T = 293 K

KW - wR factor = 0.085

UR - http://www.scopus.com/inward/record.url?scp=84863049908&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84863049908&partnerID=8YFLogxK

U2 - 10.1107/S1600536812002966

DO - 10.1107/S1600536812002966

M3 - Article

VL - 68

JO - Acta Crystallographica Section E: Structure Reports Online

JF - Acta Crystallographica Section E: Structure Reports Online

SN - 1600-5368

IS - 2

ER -