Hostname: page-component-7479d7b7d-fwgfc Total loading time: 0 Render date: 2024-07-13T16:59:46.187Z Has data issue: false hasContentIssue false

Energetics of C11b, C40, C54, and C49 structures in transition-metal disilicides

Published online by Cambridge University Press:  31 January 2011

A.E. Carlsson
Affiliation:
Department of Physics, Washington University, St. Louis, Missouri 63130
P.J. Meschter
Affiliation:
McDonnell Douglas Research Laboratories, 224/111–1041, P. O. Box 516, St. Louis, Missouri 63166
Get access

Abstract

The relative energies of the related C11b, C40, and C54 crystal structures of group IV–VII transition-metal disilicides are obtained by ab initio self-consistent band-structure calculations using the augmented-spherical-wave (ASW) method. The structural energy differences among these three structures correlate strongly with d-band filling, with C40 being stabilized relative to C54 and C11b relative to C40 as the transition-metal d-electron count increases. The C40/C11b energy difference is <0.05 eV/atom only for CrSi2 and MoSi2. Relative C11b/C40/C54 energies are similar in magnitude to those obtained in previous studies of L12/D022/D023 competition in transition-metal aluminides.1,2 Calculations of the C49/C54 energetic competition are inaccurate; the differences in atomic coordination in these two structures are probably too large for the computational method to handle accurately. The total-energy results are interpreted by a detailed analysis of the electronic density-of-states (DOS) distributions. The stable structures do not correlate as strongly with DOS effects in the vicinity of the Fermi level as in the aluminides.

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

REFERENCES

1.Carlsson, A. E. and Meschter, P. J., J. Mater. Res. 4, 1060 (1989).CrossRefGoogle Scholar
2.Carlsson, A. E. and Meschter, P. J., J. Mater. Res. 5, 2813 (1990).CrossRefGoogle Scholar
3.Schlichting, J., High Temp.-High Press. 10, 241 (1978).Google Scholar
4.Meschter, P.J. and Schwartz, D.S., JOM 41 (11), 52 (1989).CrossRefGoogle Scholar
5.Fitzer, E., Herbst, H., and Schlichting, J., Werkst. Korros. 24, 274 (1973).CrossRefGoogle Scholar
6.Umakoshi, Y., Hirano, T., Sakagami, T., and Yamane, T., Scripta Metall. 23, 87 (1989).CrossRefGoogle Scholar
7.Umakoshi, Y., Sakagami, T., Yamane, T., and Hirano, T., Philos. Mag. Lett. A 59, 159 (1989).CrossRefGoogle Scholar
8.Umakoshi, Y., Sakagami, T., Hirano, T., and Yamane, T., Acta Metall. Mater. 38, 909 (1990).CrossRefGoogle Scholar
9.Weaver, J.H., Moruzzi, V.L., and Schmidt, F. A., Phys. Rev. B 23, 2916 (1981).CrossRefGoogle Scholar
10.Bhattacharya, B. K., Bylander, D. M., and Kleinman, L., Phys. Rev. B 32, 7973 (1985).CrossRefGoogle Scholar
11.Speier, W., Kumar, L., Sarma, D.D., de Groot, R.A., and Fuggle, J.C., J. Phys.: Condens. Matter 1, 9117 (1989).Google Scholar
12.Itoh, S., Mater. Sei. Eng. B6, 37 (1990).CrossRefGoogle Scholar
13.Williams, A.R., Kubier, J., and Gelatt, C.D., Phys. Rev. B 19, 6094 (1979).CrossRefGoogle Scholar
14.Methfessel, M. and Kubier, J., J. Phys. F12, 141 (1982).CrossRefGoogle Scholar
15.Villars, P. and Calvert, L. D., Pearson's Handbook of Crystallography Data for Intermetallic Phases (ASM, Metals Park, OH, 1986).Google Scholar
16.Svechnikov, V.N., Kocherzhinskii, Y.A., and Yupko, L. M., in Diagrammy Sostoyaniya Metal Sist. Nauka, edited by Ageev, V. N. (Moscow, 1971), p. 116.Google Scholar
17.Pearson, W. D., The Crystal Chemistry and Physics of Metals and Alloys (Wiley, New York, 1972).Google Scholar
18.Xu, J-H. and Freeman, A. J., Phys. Rev. B 40, 11927 (1989).CrossRefGoogle Scholar
19.Frankwicz, P.S. and Perepezko, J.H., Symposium on High-Temperature Ordered Intermetallic Alloys, MRS Fall Meeting, Boston, MA (1990).Google Scholar
20.Nowotny, H., Kieffer, R., and Schachner, H., Monatsh. Chemie 83, 1243 (1952).CrossRefGoogle Scholar
21.Senemaud, C., Vergand, F., Bonnelle, C., Thomas, O., Senateur, J. P., and Madar, R., Solid State Commun. 64, 129 (1987).CrossRefGoogle Scholar
22. See, for instance, Jones, R. O. and Gunnarsson, O., Rev. Mod. Phys. 61, 689 (1989).CrossRefGoogle Scholar
23.Cyrot-Lackmann, F., J. Phys. Chem. Solids 29, 1235 (1968).CrossRefGoogle Scholar
24.Yu, J., Freeman, A.J., and Xu, J-H., Phys. Rev. Lett. 58, 1035 (1987), and references therein.CrossRefGoogle Scholar