Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-18T05:24:35.570Z Has data issue: false hasContentIssue false

Electron microscope study of the structure of SrMnO3−x with planar defect

Published online by Cambridge University Press:  08 February 2011

H. Shibahara
Affiliation:
Department of Chemistry, Kyoto University of Education, Fushimi-ku, Kyoto 612, Japan
Get access

Abstract

Structures of some phases in the SrMnO3−x system accompanied by planar defect were studied using a high resolution electron microscope. A four-layer structure with a hexagonal unit cell was found to have an oxygen deficiency in some degree followed by planar defects normal to the c-axis which are classified into several types. On the basis of observed images showing an irregular stacking along the c-axis in the hexagonal unit, the distribution and the origin of the planar defect are discussed. A structure image showed the transformation of the four-layer phase into a nonstoichiometric state and a shear structure with a displacement vector of occurring between the face-sharing octahedra. Experiment by in situ observation during beam irradiation in an electron microscope indicates the process of the formation of the planar defect. A mechanism for the formation of the planar defect is proposed by which oxygen deficiency in face-sharing octahedra induces the displacement of SrO3 layers and oxygen octahedra which reduce the coordination number of Mn ions and the disruption of face-sharing octahedra.

Type
Articles
Copyright
Copyright © Materials Research Society 1991

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1Syono, Y., Akimoto, S., and Kohn, K., J. Phys. Soc. Jpn. 26, 993 (1969).CrossRefGoogle Scholar
2Negas, T. and Roth, R. S., J. Solid State Chem. 3, 323 (1971).CrossRefGoogle Scholar
3Chamberland, B. L., Sleight, A. W., and Weiher, J. F., J. Solid State Chem. 1, 507 (1970).Google Scholar
4Hardy, A., Acta Crystallogr. Sect. B15, 179 (1962).Google Scholar
5Negas, T. and Roth, R. S., J. Solid State Chem. 1, 409 (1970).CrossRefGoogle Scholar
6Caignaert, V., Hervieu, M., Nguyen, N., and Raveau, B., J. Solid State Chem. 62, 281 (1986).CrossRefGoogle Scholar
Shibahara, H. and Hashimoto, H., in Proc. 7th Int. Conf. on Crystal Growth, Stuttgart, J. Cryst. Growth 65, 683 (1983).Google Scholar
8Shibahara, H., J. Solid State Chem. 69, 81 (1987).CrossRefGoogle Scholar
9Shibahara, H., J. Solid State Chem. 66, 116 (1987).CrossRefGoogle Scholar
10Shibahara, H., J. Solid State Chem. 81, 40 (1989).CrossRefGoogle Scholar
11Mizutani, M., Okura, V., Kitazawa, A., and Kato, M., J. Chem. Soc. Jpn. Ind. Chem. Soc. 73, 1103 (1970).Google Scholar
12Cowely, J. M. and Moodie, A. F., Acta Crystallogr. 10, 609 (1957).CrossRefGoogle Scholar
13Goodman, P. and Moodie, A. F., Acta Crystallogr. Sect. A30, 280 (1974).CrossRefGoogle Scholar
14Shannon, R. D. and Prewitt, C. T., Acta Crystallogr. Sect. B25, 925 (1969).CrossRefGoogle Scholar