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Title: The structure and ordering of {epsilon}-MnO{sub 2}

Abstract

The presence of {epsilon}-MnO{sub 2} as a major component of electrolytic manganese dioxide (EMD) has been demonstrated by a combined X-ray diffraction/transmission electron microscopy (TEM) study. {epsilon}-MnO{sub 2} usually has a partially ordered defect NiAs structure containing 50% cation vacancies; these vacancies can be fully ordered by a low temperature (200 deg. C) heat treatment to form a pseudohexagonal but monoclinic superlattice. Numerous fine-scale anti-phase domain boundaries are present in ordered {epsilon}-MnO{sub 2} and cause extensive peak broadening and a massive shift of a very intense, 0.37 nm superlattice peak. This suggests a radically different explanation of the ubiquitous, very broad {approx}0.42 nm peak ({approx}21-22 deg. 2{theta}, CuK{alpha} radiation) in EMDs, which heretofore has been attributed to Ramsdellite containing numerous planar defects. This work confirms the multi-phase model of equiaxed EMDs proposed by Heuer et al. [ITE Lett. 1(6) (2000) B50; Proc. Seventh Int. Symp. Adv. Phys. Fields 92 (2001)], rather than the defective single-phase model of Chabre and Pannetier [Prog. Solid State Chem. 23 (1995) 1] and Bowden et al. [ITE Lett. 4(1) (2003) B1].

Authors:
 [1];  [1];  [1];  [2];  [3];  [4]
  1. Department of Materials Science and Engineering, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106-7204 (United States)
  2. Department of Materials Science and Engineering, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106-7204 (United States). E-mail: heuer@case.edu
  3. Physical Sciences Inc., 20 New England Business Center, Andover, MA 01810 (United States)
  4. Energizer Battery Manufacturing, 25225 Detroit Rd., Westlake, OH 44145 (United States)
Publication Date:
OSTI Identifier:
20784919
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 179; Journal Issue: 3; Other Information: DOI: 10.1016/j.jssc.2005.11.042; PII: S0022-4596(05)00573-6; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; HEAT TREATMENTS; MANGANESE OXIDES; MONOCLINIC LATTICES; SUPERLATTICES; TEMPERATURE RANGE 0400-1000 K; TRANSMISSION ELECTRON MICROSCOPY; VACANCIES; X-RAY DIFFRACTION

Citation Formats

Kim, Chang-Hoon, Akase, Zentaro, Zhang Lichun, Heuer, Arthur H., Newman, Aron E., and Hughes, Paula J.. The structure and ordering of {epsilon}-MnO{sub 2}. United States: N. p., 2006. Web. doi:10.1016/j.jssc.2005.11.042.
Kim, Chang-Hoon, Akase, Zentaro, Zhang Lichun, Heuer, Arthur H., Newman, Aron E., & Hughes, Paula J.. The structure and ordering of {epsilon}-MnO{sub 2}. United States. doi:10.1016/j.jssc.2005.11.042.
Kim, Chang-Hoon, Akase, Zentaro, Zhang Lichun, Heuer, Arthur H., Newman, Aron E., and Hughes, Paula J.. Wed . "The structure and ordering of {epsilon}-MnO{sub 2}". United States. doi:10.1016/j.jssc.2005.11.042.
@article{osti_20784919,
title = {The structure and ordering of {epsilon}-MnO{sub 2}},
author = {Kim, Chang-Hoon and Akase, Zentaro and Zhang Lichun and Heuer, Arthur H. and Newman, Aron E. and Hughes, Paula J.},
abstractNote = {The presence of {epsilon}-MnO{sub 2} as a major component of electrolytic manganese dioxide (EMD) has been demonstrated by a combined X-ray diffraction/transmission electron microscopy (TEM) study. {epsilon}-MnO{sub 2} usually has a partially ordered defect NiAs structure containing 50% cation vacancies; these vacancies can be fully ordered by a low temperature (200 deg. C) heat treatment to form a pseudohexagonal but monoclinic superlattice. Numerous fine-scale anti-phase domain boundaries are present in ordered {epsilon}-MnO{sub 2} and cause extensive peak broadening and a massive shift of a very intense, 0.37 nm superlattice peak. This suggests a radically different explanation of the ubiquitous, very broad {approx}0.42 nm peak ({approx}21-22 deg. 2{theta}, CuK{alpha} radiation) in EMDs, which heretofore has been attributed to Ramsdellite containing numerous planar defects. This work confirms the multi-phase model of equiaxed EMDs proposed by Heuer et al. [ITE Lett. 1(6) (2000) B50; Proc. Seventh Int. Symp. Adv. Phys. Fields 92 (2001)], rather than the defective single-phase model of Chabre and Pannetier [Prog. Solid State Chem. 23 (1995) 1] and Bowden et al. [ITE Lett. 4(1) (2003) B1].},
doi = {10.1016/j.jssc.2005.11.042},
journal = {Journal of Solid State Chemistry},
number = 3,
volume = 179,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
  • We studied three distorted perovskite manganites, Pr{sub 1/2}Sr {sub 1/2}MnO {sub 3} and Nd{sub 1-x}Sr {sub x}MnO{sub 3} with x=1/2 and 0.55 by the neutron diffraction technique. Two samples with x=1/2 exhibit a transition from a ferromagnetic (FM) metal to an antiferromagnetic (AFM) nonmetal. We demonstrate that, in the low temperature phase, Nd{sub 1/2}Sr {sub 1/2}MnO {sub 3} has a CE-type AFM structure with charge ordering, while Pr{sub 1/2}Sr {sub 1/2}MnO {sub 3} and Nd{sub 0.45} Sr{sub 0.55} MnO{sub 3} exhibit an A-type layered AFM structure, but show no clear sign of charge ordering. From the present results, we suggestmore » a possible anisotropy of transport as well as magnetic properties in the A-type AFM structure near x{approximately}1/2. {copyright} {ital 1997} {ital The American Physical Society}« less
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  • tau-Ag{sub 1/2}Cu{sub 1/2}V{sub 2}O{sub 5} compound crystallises in the monoclinic system space group C2/m with cell parameters a=11.757(4) A, b=3.6942(5) A, c=9.463(2) A, and beta=114.62(2){sup o}. The structure is build up with V{sub 4}O{sub 10} D4 double layer. The silver and copper ions are located in two different oxygenated tunnels. Examination of electronic density maps shows that while the silver ions are located in defined crystallographic sites, the copper ones are fully delocalised over the whole tunnel. Comparison with delta-Ag{sub x}V{sub 2}O{sub 5} and epsilon-Cu{sub x}V{sub 2}O{sub 5} refined structure allows to define crystal chemistry parameters governing the ionic delocalisationmore » and give clues to predict from structural consideration the expected electrical behaviour with the aim to make possible a structural design to enhance guest species reactivity. - Graphical abstract: The role of nature and amount of guest species on their respective localisation Evidence for full delocalisation of copper ions and diffusion pathways visualisation Display Omitted« less
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