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Title: Charge states of Ca atoms in {beta}-dicalcium silicate

Abstract

In order to study the crystal structure of {beta}-bar Ca{sub 2}SiO{sub 4}, time-of-flight neutron powder diffraction experiments were carried out at temperatures between room temperature (RT) and 600 deg. C. Rietveld refinement at RT has shown that {beta}-bar Ca{sub 2}SiO{sub 4} is monoclinic based on P2{sub 1}/n symmetry and two different types of Ca sites, Ca(1) and Ca(2). All interatomic distances within 3A were calculated, with the valences of Ca(1) with seven Ca-O bonds and Ca(2) with eight were estimated to be 1.87+ and 2+ by the Zachariasen-Brown-Altermatt formula (bond valence sum). Applying charge neutrality the two charge states of Ca in {beta}-bar Ca{sub 2}SiO{sub 4} are [Ca(1)SiO{sub 4}]{sup 2-} and Ca(2){sup 2+}, respectively. Furthermore, the [Ca(1)SiO{sub 4}]{sup 2-} unit has the shortest Ca-O distance, and its length kept constant at 2.23A at all temperatures. In the short-range structure analysis at RT, the shortest Ca-O bond was also observed in a radial distribution function. These results imply that the [Ca(1)SiO{sub 4}]{sup 2-} unit has covalency on the shortest Ca-O in addition to Si-O.

Authors:
 [1];  [2];  [3];  [4];  [5];  [1];  [1];  [6];  [1]
  1. Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan)
  2. Intense Pulsed Neutron Source Division, Argonne National Laboratory, Argonne, IL 60439 (United States)
  3. Institute of Applied Beam Science, Graduate School of Engineering and Science, Ibaraki University, 4-12-1 Nakanarusawa-cho, Hitach, Ibaraki 316-8511 (Japan)
  4. Department of Materials Structure Science, Graduate University for Advanced Studies, Tsukuba, Ibaraki 305-0801 (Japan)
  5. Department of Engineering Physics and Mechanics, Kyoto University, Kyoto 606-8501 (Japan)
  6. Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 (Japan)
Publication Date:
OSTI Identifier:
20900872
Resource Type:
Journal Article
Journal Name:
Journal of Solid State Chemistry
Additional Journal Information:
Journal Volume: 179; Journal Issue: 11; Other Information: DOI: 10.1016/j.jssc.2006.06.018; PII: S0022-4596(06)00356-2; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energyncy (IAEA)CALC; Journal ID: ISSN 0022-4596
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CALCIUM SILICATES; CHARGE STATES; INTERATOMIC DISTANCES; MONOCLINIC LATTICES; NEUTRON DIFFRACTION; SPATIAL DISTRIBUTION; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K; TIME-OF-FLIGHT METHOD; VALENCE

Citation Formats

Mori, Kazuhiro, Kiyanagi, Ryoji, Yonemura, Masao, Iwase, Kenji, Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801, Sato, Takashi, Itoh, Keiji, Sugiyama, Masaaki, Kamiyama, Takashi, and Fukunaga, Toshiharu. Charge states of Ca atoms in {beta}-dicalcium silicate. United States: N. p., 2006. Web. doi:10.1016/j.jssc.2006.06.018.
Mori, Kazuhiro, Kiyanagi, Ryoji, Yonemura, Masao, Iwase, Kenji, Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801, Sato, Takashi, Itoh, Keiji, Sugiyama, Masaaki, Kamiyama, Takashi, & Fukunaga, Toshiharu. Charge states of Ca atoms in {beta}-dicalcium silicate. United States. https://doi.org/10.1016/j.jssc.2006.06.018
Mori, Kazuhiro, Kiyanagi, Ryoji, Yonemura, Masao, Iwase, Kenji, Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801, Sato, Takashi, Itoh, Keiji, Sugiyama, Masaaki, Kamiyama, Takashi, and Fukunaga, Toshiharu. 2006. "Charge states of Ca atoms in {beta}-dicalcium silicate". United States. https://doi.org/10.1016/j.jssc.2006.06.018.
@article{osti_20900872,
title = {Charge states of Ca atoms in {beta}-dicalcium silicate},
author = {Mori, Kazuhiro and Kiyanagi, Ryoji and Yonemura, Masao and Iwase, Kenji and Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 and Sato, Takashi and Itoh, Keiji and Sugiyama, Masaaki and Kamiyama, Takashi and Fukunaga, Toshiharu},
abstractNote = {In order to study the crystal structure of {beta}-bar Ca{sub 2}SiO{sub 4}, time-of-flight neutron powder diffraction experiments were carried out at temperatures between room temperature (RT) and 600 deg. C. Rietveld refinement at RT has shown that {beta}-bar Ca{sub 2}SiO{sub 4} is monoclinic based on P2{sub 1}/n symmetry and two different types of Ca sites, Ca(1) and Ca(2). All interatomic distances within 3A were calculated, with the valences of Ca(1) with seven Ca-O bonds and Ca(2) with eight were estimated to be 1.87+ and 2+ by the Zachariasen-Brown-Altermatt formula (bond valence sum). Applying charge neutrality the two charge states of Ca in {beta}-bar Ca{sub 2}SiO{sub 4} are [Ca(1)SiO{sub 4}]{sup 2-} and Ca(2){sup 2+}, respectively. Furthermore, the [Ca(1)SiO{sub 4}]{sup 2-} unit has the shortest Ca-O distance, and its length kept constant at 2.23A at all temperatures. In the short-range structure analysis at RT, the shortest Ca-O bond was also observed in a radial distribution function. These results imply that the [Ca(1)SiO{sub 4}]{sup 2-} unit has covalency on the shortest Ca-O in addition to Si-O.},
doi = {10.1016/j.jssc.2006.06.018},
url = {https://www.osti.gov/biblio/20900872}, journal = {Journal of Solid State Chemistry},
issn = {0022-4596},
number = 11,
volume = 179,
place = {United States},
year = {Wed Nov 15 00:00:00 EST 2006},
month = {Wed Nov 15 00:00:00 EST 2006}
}