Investigation of hardness in tetrahedrally bonded nonmolecular CO2 solids by density-functional theory

J. Dong, J. K. Tomfohr, O. F. Sankey, Kurt Leinenweber, M. Somayazulu, P. F. McMillan

Research output: Contribution to journalArticle

64 Citations (Scopus)

Abstract

Stability and compressibility of several nonmolecular (polymeric) CO2 solids in structures analogous to those of SiO2 have been investigated with ab initio density-functional theory. Contrary to the recent experimental reports of a "superhard" high-pressure tridymite form of CO2, we find that metastable tetrahedrally bonded CO2 polymorphs, such as tridymite, cristobalite, and quartz, are relatively compressible, with bulk moduli K of only 1/2 to 1/3 of the reported experimental value. In addition, theory finds that the experimentally reported lattice parameters are not stable for CO2 P212121 tridymite. Finally, none of the calculated x-ray spectra of the fully relaxed structures of CO2 polymorphs obtained from theory agrees with the experiments. The significant discrepancy between experiments and density-functional theory suggests that further studies on nonmolecular CO2 solids are necessary, and that the assumptions that density-functional theory can describe these materials correctly, or that the framework of the new nonmolecular CO2 solids contains only CO4 tetrahedra, must be re-examined.

Original languageEnglish (US)
Pages (from-to)14685-14689
Number of pages5
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume62
Issue number22
DOIs
StatePublished - Dec 1 2000
Externally publishedYes

Fingerprint

Silicon Dioxide
Density functional theory
hardness
Hardness
density functional theory
Polymorphism
x ray spectra
bulk modulus
Compressibility
tetrahedrons
Quartz
compressibility
Lattice constants
lattice parameters
quartz
Elastic moduli
Experiments
X rays

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Investigation of hardness in tetrahedrally bonded nonmolecular CO2 solids by density-functional theory. / Dong, J.; Tomfohr, J. K.; Sankey, O. F.; Leinenweber, Kurt; Somayazulu, M.; McMillan, P. F.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 62, No. 22, 01.12.2000, p. 14685-14689.

Research output: Contribution to journalArticle

Dong, J. ; Tomfohr, J. K. ; Sankey, O. F. ; Leinenweber, Kurt ; Somayazulu, M. ; McMillan, P. F. / Investigation of hardness in tetrahedrally bonded nonmolecular CO2 solids by density-functional theory. In: Physical Review B - Condensed Matter and Materials Physics. 2000 ; Vol. 62, No. 22. pp. 14685-14689.
@article{c4a9294253af40729e2b5d8e00b20a1f,
title = "Investigation of hardness in tetrahedrally bonded nonmolecular CO2 solids by density-functional theory",
abstract = "Stability and compressibility of several nonmolecular (polymeric) CO2 solids in structures analogous to those of SiO2 have been investigated with ab initio density-functional theory. Contrary to the recent experimental reports of a {"}superhard{"} high-pressure tridymite form of CO2, we find that metastable tetrahedrally bonded CO2 polymorphs, such as tridymite, cristobalite, and quartz, are relatively compressible, with bulk moduli K of only 1/2 to 1/3 of the reported experimental value. In addition, theory finds that the experimentally reported lattice parameters are not stable for CO2 P212121 tridymite. Finally, none of the calculated x-ray spectra of the fully relaxed structures of CO2 polymorphs obtained from theory agrees with the experiments. The significant discrepancy between experiments and density-functional theory suggests that further studies on nonmolecular CO2 solids are necessary, and that the assumptions that density-functional theory can describe these materials correctly, or that the framework of the new nonmolecular CO2 solids contains only CO4 tetrahedra, must be re-examined.",
author = "J. Dong and Tomfohr, {J. K.} and Sankey, {O. F.} and Kurt Leinenweber and M. Somayazulu and McMillan, {P. F.}",
year = "2000",
month = "12",
day = "1",
doi = "10.1103/PhysRevB.62.14685",
language = "English (US)",
volume = "62",
pages = "14685--14689",
journal = "Physical Review B-Condensed Matter",
issn = "0163-1829",
publisher = "American Institute of Physics Publising LLC",
number = "22",

}

TY - JOUR

T1 - Investigation of hardness in tetrahedrally bonded nonmolecular CO2 solids by density-functional theory

AU - Dong, J.

AU - Tomfohr, J. K.

AU - Sankey, O. F.

AU - Leinenweber, Kurt

AU - Somayazulu, M.

AU - McMillan, P. F.

PY - 2000/12/1

Y1 - 2000/12/1

N2 - Stability and compressibility of several nonmolecular (polymeric) CO2 solids in structures analogous to those of SiO2 have been investigated with ab initio density-functional theory. Contrary to the recent experimental reports of a "superhard" high-pressure tridymite form of CO2, we find that metastable tetrahedrally bonded CO2 polymorphs, such as tridymite, cristobalite, and quartz, are relatively compressible, with bulk moduli K of only 1/2 to 1/3 of the reported experimental value. In addition, theory finds that the experimentally reported lattice parameters are not stable for CO2 P212121 tridymite. Finally, none of the calculated x-ray spectra of the fully relaxed structures of CO2 polymorphs obtained from theory agrees with the experiments. The significant discrepancy between experiments and density-functional theory suggests that further studies on nonmolecular CO2 solids are necessary, and that the assumptions that density-functional theory can describe these materials correctly, or that the framework of the new nonmolecular CO2 solids contains only CO4 tetrahedra, must be re-examined.

AB - Stability and compressibility of several nonmolecular (polymeric) CO2 solids in structures analogous to those of SiO2 have been investigated with ab initio density-functional theory. Contrary to the recent experimental reports of a "superhard" high-pressure tridymite form of CO2, we find that metastable tetrahedrally bonded CO2 polymorphs, such as tridymite, cristobalite, and quartz, are relatively compressible, with bulk moduli K of only 1/2 to 1/3 of the reported experimental value. In addition, theory finds that the experimentally reported lattice parameters are not stable for CO2 P212121 tridymite. Finally, none of the calculated x-ray spectra of the fully relaxed structures of CO2 polymorphs obtained from theory agrees with the experiments. The significant discrepancy between experiments and density-functional theory suggests that further studies on nonmolecular CO2 solids are necessary, and that the assumptions that density-functional theory can describe these materials correctly, or that the framework of the new nonmolecular CO2 solids contains only CO4 tetrahedra, must be re-examined.

UR - http://www.scopus.com/inward/record.url?scp=0034452082&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0034452082&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.62.14685

DO - 10.1103/PhysRevB.62.14685

M3 - Article

VL - 62

SP - 14685

EP - 14689

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 0163-1829

IS - 22

ER -