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Title: Spinel and post-spinel phase assemblages in Zn 2TiO 4: an experimental and theoretical study

Abstract

Zn2TiO4 spinel (Zn2TiO4-Sp) was synthesized by a solid-state reaction method (1573 K, room P and 72 h) and quasi-hydrostatically compressed to ~24 GPa using a DAC coupled with a synchrotron X-ray radiation (ambient T). We found that the Zn2TiO4-Sp was stable up to ~21 GPa and transformed to another phase at higher P. With some theoretical simulations, we revealed that this high-P phase adopted the CaTi2O4-type structure (Zn2TiO4-CT). Additionally, the isothermal bulk modulus (KT) of the Zn2TiO4-Sp was experimentally obtained as 156.0(44) GPa and theoretically obtained as 159.1(4) GPa, with its first pressure derivative K'TKT' as 3.8(6) and 4.37(4), respectively. The volumetric and axial isothermal bulk moduli of the Zn2TiO4-CT were theoretically obtained as KT = 150(2) GPa (K'TKT' = 5.4(2); for the volume), KT-a = 173(2) GPa (K'T-aKT-a' = 3.9(1); for the a-axis), KT-b = 74(2) GPa (K'T-bKT-b' = 7.0(2); for the b-axis), and KT-c = 365(8) GPa (K'T-cKT-c' = 1.5(4); for the c-axis), indicating a strong elastic anisotropy. The Zn2TiO4-CT was found as ~10.0 % denser than the Zn2TiO4-Sp at ambient conditions. The spinel and post-spinel phase assemblages for the Zn2TiO4 composition at high T have been deduced as Zn2TiO4-Sp, ZnTiO3-ilmenite + ZnO-wurtzite, ZnTiO3-ilmenite + ZnO-rock salt, ZnTiO3-perovskitemore » + ZnO-rock salt, and Zn2TiO4-CT as P increases, which presumably implies a potential stability field for a CT-type Mg2SiO4 at very high P.« less

Authors:
; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
USDOE
OSTI Identifier:
1343127
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics and Chemistry of Minerals; Journal Volume: 44; Journal Issue: 2
Country of Publication:
United States
Language:
ENGLISH
Subject:
36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; compressibility; DFT calculations; diamond-anvil cell; high-P phase transition; synchrotron x-ray diffraction; Zn2TiO4-CT; Zn2TiO4-Sp

Citation Formats

Zhang, Yanyao, Liu, Xi, Shieh, Sean R., Bao, Xinjian, Xie, Tianqi, Wang, Fei, Zhang, Zhigang, Prescher, Clemens, and Prakapenka, Vitali B.. Spinel and post-spinel phase assemblages in Zn2TiO4: an experimental and theoretical study. United States: N. p., 2016. Web. doi:10.1007/s00269-016-0841-6.
Zhang, Yanyao, Liu, Xi, Shieh, Sean R., Bao, Xinjian, Xie, Tianqi, Wang, Fei, Zhang, Zhigang, Prescher, Clemens, & Prakapenka, Vitali B.. Spinel and post-spinel phase assemblages in Zn2TiO4: an experimental and theoretical study. United States. doi:10.1007/s00269-016-0841-6.
Zhang, Yanyao, Liu, Xi, Shieh, Sean R., Bao, Xinjian, Xie, Tianqi, Wang, Fei, Zhang, Zhigang, Prescher, Clemens, and Prakapenka, Vitali B.. 2016. "Spinel and post-spinel phase assemblages in Zn2TiO4: an experimental and theoretical study". United States. doi:10.1007/s00269-016-0841-6.
@article{osti_1343127,
title = {Spinel and post-spinel phase assemblages in Zn2TiO4: an experimental and theoretical study},
author = {Zhang, Yanyao and Liu, Xi and Shieh, Sean R. and Bao, Xinjian and Xie, Tianqi and Wang, Fei and Zhang, Zhigang and Prescher, Clemens and Prakapenka, Vitali B.},
abstractNote = {Zn2TiO4 spinel (Zn2TiO4-Sp) was synthesized by a solid-state reaction method (1573 K, room P and 72 h) and quasi-hydrostatically compressed to ~24 GPa using a DAC coupled with a synchrotron X-ray radiation (ambient T). We found that the Zn2TiO4-Sp was stable up to ~21 GPa and transformed to another phase at higher P. With some theoretical simulations, we revealed that this high-P phase adopted the CaTi2O4-type structure (Zn2TiO4-CT). Additionally, the isothermal bulk modulus (KT) of the Zn2TiO4-Sp was experimentally obtained as 156.0(44) GPa and theoretically obtained as 159.1(4) GPa, with its first pressure derivative K'TKT' as 3.8(6) and 4.37(4), respectively. The volumetric and axial isothermal bulk moduli of the Zn2TiO4-CT were theoretically obtained as KT = 150(2) GPa (K'TKT' = 5.4(2); for the volume), KT-a = 173(2) GPa (K'T-aKT-a' = 3.9(1); for the a-axis), KT-b = 74(2) GPa (K'T-bKT-b' = 7.0(2); for the b-axis), and KT-c = 365(8) GPa (K'T-cKT-c' = 1.5(4); for the c-axis), indicating a strong elastic anisotropy. The Zn2TiO4-CT was found as ~10.0 % denser than the Zn2TiO4-Sp at ambient conditions. The spinel and post-spinel phase assemblages for the Zn2TiO4 composition at high T have been deduced as Zn2TiO4-Sp, ZnTiO3-ilmenite + ZnO-wurtzite, ZnTiO3-ilmenite + ZnO-rock salt, ZnTiO3-perovskite + ZnO-rock salt, and Zn2TiO4-CT as P increases, which presumably implies a potential stability field for a CT-type Mg2SiO4 at very high P.},
doi = {10.1007/s00269-016-0841-6},
journal = {Physics and Chemistry of Minerals},
number = 2,
volume = 44,
place = {United States},
year = 2016,
month = 9
}
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