Hostname: page-component-84b7d79bbc-fnpn6 Total loading time: 0 Render date: 2024-07-30T07:37:28.615Z Has data issue: false hasContentIssue false

Neutron powder diffraction study of the products from fluorinating YBa2Cu3O7−s at room temperature and at 400 °C

Published online by Cambridge University Press:  31 January 2011

E. Garcia
Affiliation:
Los Alamos National Laboratory, Los Alamos, New Mexico 87545
N. N. Sauer
Affiliation:
Los Alamos National Laboratory, Los Alamos, New Mexico 87545
R. R. Ryan
Affiliation:
Los Alamos National Laboratory, Los Alamos, New Mexico 87545
A. Williams
Affiliation:
Los Alamos National Laboratory, Los Alamos, New Mexico 87545
P. G. Eller
Affiliation:
Los Alamos National Laboratory, Los Alamos, New Mexico 87545
Get access

Abstract

Fluorination of YBa2Cu3O7−s at room temperature results in no change of the critical temperature but a drastic reduction of superconducting volume fraction as determined by magnetic flux exclusion measurements. Rietveld refinement of neutron powder diffraction data indicates that the bulk structure has not changed in any significant way despite the loss of superconductivity. In marked contrast, when the superconducting oxide is fluorinated at 400 °C, a structural transformation from orthorhombic to tetragonal symmetry occurs that is accompanied by essentially complete filling of eight of the nine perovskite anion sites and total loss of superconductivity above 7 K. Interpretation of neutron activation analysis and neutron diffraction results render the formula of the fluorinated product as YBa2Cu3F3.5O4.5, but fluoride ions in the unit cell were not distinguished from oxide ions.

Type
Articles
Copyright
Copyright © Materials Research Society 1988

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

REFERENCES

1Bednorz, J. G. and Muller, K. A., Z. Phys. B 64, 189 (1986).Google Scholar
2Chu, C. W., Hor, P. H., Meng, R. L., Gao, L., Hung, Z. J., and Wang, Y. Z., Phys. Rev. Lett. 58, 405 (1987).Google Scholar
3Wu, M. K., Ashburn, J. R., Torng, C. J., Hor, P. H., Meng, R. L., Gao, L., Huang, Z. J., Wang, Y. Q., and Chu, C. W., Phys. Rev. Lett. 58, 908 (1987).Google Scholar
4Ovshinsky, S. R., Young, R. T., Allred, D. D., DeMaggio, G., and Leeden, G. A. van der, Phys. Rev. Lett. 58, 2579 (1987).Google Scholar
5Xian-Ren, H., Yan-Ru, R., Ming-Zhu, L., Quing-Yun, T., ZhenRen, L., Li-Hua, S., Wei-Qing, D., Min-Hua, F., Qing-Yun, M., ChangJiang, L., Xiu-Rai, L., Guan-Liang, Q., and Mou-Yuan, C., International Symposium on High Tc Superconductors, Beijing, Peoples Republic of China (1987).Google Scholar
6Bhargava, R. N., Herko, S. P., and Osborne, W. N., Phys. Rev. Lett. 59, 1468 (1987).Google Scholar
7Tissue, B. M., Cirillo, K. M., Wright, J. C., Daeumling, M., and Larbalestier, D. C., Solid State Commun. 65, 51 (1988).CrossRefGoogle Scholar
8Sauer, N. N., Garcia, E., Martin, J. A., Ryan, R. R., Eller, P. G., Tesmer, J. R., and Maggiore, C. J., J. Mater. Res. 3, 813 (1988).CrossRefGoogle Scholar
9Larson, A. C. and Dreele, R. B. Von, “GSAS—Generalized Crystal Structure Analysis System,” LA-UR-86-748, Los Alamos National Laboratory (1987).Google Scholar
10Beno, M. A., Soderholm, L., Capone, D. W. II , Hinks, D. G., Jorgensen, J. D., and Schuller, I. K., Appl. Phys. Lett. 51, 57 (1987).Google Scholar
11Beech, F., Miraglia, S., Santoro, A., and Roth, R. S., Phys. Rev. B 35, 8778 (1987).Google Scholar
12Capponi, J. J., Chaillout, C., Hewat, A. W., Lejay, P., Marezio, M., Nguyen, N., Raveau, B., Soubeyroux, J. L., Tholence, J. L., and Tournier, R., Europhys. Lett. 3, 1301 (1987).CrossRefGoogle Scholar
13Greedan, J. E., O'Reilly, A. H., and Stager, C. V., Phys. Rev. B 35, 8770 (1987).Google Scholar
14Williams, A., Kwei, G. H., Dreele, R. B. Von, Raistrick, I. D., and Bish, D. L., J. Phys. Rev. (submitted) (1988).Google Scholar
15Santoro, A., Miraglia, S., Beech, F., Sunshine, S. A., Murphy, D. W., Schneemeyer, L. F., and Waszczak, J. V., Mater. Res. Bull. 22, 1007 (1987).Google Scholar