Hostname: page-component-8448b6f56d-c4f8m Total loading time: 0 Render date: 2024-04-18T23:22:05.927Z Has data issue: false hasContentIssue false

Effect of Co3+ Ion on Metal-Insulator Transition in (La0.1Ca0.9)(Mn1-xCox)O3

Published online by Cambridge University Press:  16 February 2011

Hideki Taguchi*
Affiliation:
Research Laboratory for Surface Science, Faculty of Science, Okayama University, Okayama 700-8530, Japan, htaguchi@cc.okayama-u.ac.jp
Get access

Abstract

Orthorhombic perovskite-type (La0.1Ca0.9)(Mn1-xCox)O3 was synthesized in the range 0.00 ≤ x ≤ 0.08. The Rietveld analysis indicates that the (Mn, Co)-O(1 and 2) distances are independent of the composition (x). Measurements of the electrical resistivity (ρ) and the Seebeck coefficient (α) indicate that (La0.1Ca0.9)(Mn1-xCox)O3 is an n-type semiconductor at the low temperature. At the high temperature, (La0.1Ca0.9)(Mn1-xCox)O3 exhibits a metal-insulator transition in the range 0.0 ≤ x ≤ 0.04. The metal-insulator transition temperature (Tt) increases with increasing the Co3+ ion content, while dρ/dT in the metallic region decreases with increasing the Co3+ ion content. The variation of Ea and T+ is explained by the difference in the electronegativity between Mn and Co atoms. The variation of dρ/dT in the metallic region is explained by the increase in the collective o bond.

Type
Research Article
Copyright
Copyright © Materials Research Society 1999

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

1. Taguchi, H. and Shimada, M., J. Solid State Chem. 63, 290 (1986).Google Scholar
2. Taguchi, H., Nagao, M., and Shimada, M., J. Solid State Chem. 97, 476 (1992).Google Scholar
3. Taguchi, H., J. Solid State Chem. 124, 360 (1996).Google Scholar
4. Taguchi, H., Sonoda, M., Nagao, M., and Kido, H., J. Solid State Chem. 126, 235 (1996).Google Scholar
5. Taguchi, H., Sonoda, M., and Nagao, M., J. Solid State Chem. (in press)Google Scholar
6. Izumi, F., The Rietveld Method, (Oxford Press, Oxford, 1993), pp. 236253.Google Scholar
7. Poeppelmeier, K. R., Leonowicz, M. E., Scanlon, J. C., and Yelon, W. B., J. Solid State Chem. 45, 71 (1982).Google Scholar
8. Tuller, H. L. and Nowick, A. S., J. Phys. Chem. Solids 38, 859 (1977).Google Scholar
9. Goodenough, J. B., J. Appl. Phys. 37, 1415 (1966).Google Scholar
10. Goodenough, J. B., Czech. J. Phys. B 17, 304 (1967).Google Scholar
11. Gordy, W. and Thomas, W. J. O., J. Chem. Phys. 24, 439 (1956).Google Scholar
12. Pauling, L., The Nature of the Chemical Bond, (Cornell University Press, New York, 1960), pp. 88102.Google Scholar