Hostname: page-component-6bf8c574d5-w79xw Total loading time: 0 Render date: 2025-02-19T15:09:09.258Z Has data issue: false hasContentIssue false
  • English
  • Français

Line Profile Analyses of Rhodium Metal Obtained by Decomposition of Rhodium Carbonyl

Published online by Cambridge University Press:  06 March 2019

Dhanesh Chandra ,
Himanshu Mandalia ,
Michael L. Garner ,
Mary Kay Blakely  and
K. H. Lau
Dhanesh Chandra
Affiliation:
Department of Chemical and Metallurgical Engineering, Mail Stop 170 Mackay School of Mines University of Nevada, Reno NV 89557
Himanshu Mandalia
Affiliation:
Department of Chemical and Metallurgical Engineering, Mail Stop 170 Mackay School of Mines University of Nevada, Reno NV 89557
Michael L. Garner
Affiliation:
Department of Chemical and Metallurgical Engineering, Mail Stop 170 Mackay School of Mines University of Nevada, Reno NV 89557
Mary Kay Blakely
Affiliation:
U.S. Bureau of Mines, Reno Research Center 605 Evans Avenue Reno, NV 89512
K. H. Lau
Affiliation:
SRI International 333 Ravenswood Avenue Menlo Park CA 94025
Get access

Abstract

Metal carbonyls are important for chemical vapor deposition (CVD) of metals and alloys and formation of high surface area metallic particles which have potential applications as catalysts. Rhodium carbonyl [Rh6(CO)16] produces high surface area metallic particles whose structure has been reported as monoclinic (I2/a) with lattice dimensions, a=17.00(±0.03)Å, b=9.78(±0.02)Å, c=17.53(±0.03)Å and β=121°45' ± 30' at room temperature. Generally, metal carbonyl crystals dissociate under vacuum as carbonyl gas and decompose to metallic crystals and carbon monoxide at higher temperatures. However, the behavior of rhodium carbonyl crystals is different; they decompose directly to metallic rhodium without the formation of rhodium carbonyl gas in vacuum. Several residual fine grains of rhodium metal are found after the decomposition in vacuum at relatively low temperatures. The metallic samples of rhodium were obtained from vapor pressure experiments using torsion Knudsen-effusion apparatus. X-ray diffraction analyses performed on these grains showed severely broadened Bragg reflections indicative of small particle size and/or lattice microstrain. In this study, a comparison of lattice strains and domain sizes obtained by integral breadth and Fourier methods has been made. In addition a comparison of the lattice strains and domain sizes has been made between the Cauchy, Gaussian, Cauchy-Gaussian and Aqua integral breadth methods.

Type
V. Residual Stress, Crystallite Size and rms Strain Determination by Diffraction Methods
Information
Advances in X-Ray Analysis , Volume 38: Forty-third Annual Conference on Applications of X-ray Analysis , 1994 , pp. 413 - 425
Copyright
Copyright © International Centre for Diffraction Data 1994

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. Pfeifer, H.W., “ Hybrid and Selected Metal Matrix Composites ,” Chapter 6 ed.; Renton, W. J., AIAA, 12,900 Avenues of Americas, NY 1977.Google Scholar
2. Visnappu, A., US Bureau of Mines RI No.7719 , 1973.Google Scholar
3. Mittash, A.Z., Phys. Chem., vol. 490, 1902, pp 1. Also see, Mond L., Langer, C, and Quinche, F. J” J. Chem, Soc. London, vol 57, 1896, pp 749.Google Scholar
4. Lander, J.J. and Germer, L.H. AIMS Tech. Publication #2259 , Inst, of Metais Division, Metals Technology (London) 14, #6 71. pp 1, 1948,Google Scholar
5. Powell, C.F., Oxley, J. H and Blocke, J.M. “ Vapor Deposition” , John Wiley and Sons Inc. NY. Google Scholar
6. Clements, P., and Sale, F., Met. Trans B, Sept., 1976, 713 (30), pp 435.Google Scholar
7. Shorovshrov, M. Kh., et al., Adgez. Rasplavav-Packa Mater., 1976, 1, as reported in the Chem. Abst. 1978.(ref. 88:10627P,1978).Google Scholar
8. Shorovshrov, M.Kh., et al., Fix. Khim. Abrad. Mater., July 1976(4), 141–143 (Reported in Metals Abstract, 1976)Google Scholar
9. Garner, M. L. . ‘ 'Vapor Pressure and Thermodynamic Properties of W,Cr,Co and Rh Carbonyls, “ M. S. Thesis, University of Nevada, Reno, June 1994.Google Scholar
10. Margrave, J., “ Vapor Pressure Measurements at High Temperatures,” 1978,Google Scholar
11. Hildenbrand, D.L., and Knight, D.L., I Phys. Chem. vol. 51 pp 1260 1969 Google Scholar
12. Klug, H.P. and Alexander, L.E. “X-ray diffraction Procedures for Poiycrystalline and Amorphous Materials,” 2 ed., 1974, John Wiley and Sons, NY; (Chapters 5 and 9).Google Scholar
13. Balasingh, C, Abuhasan, A., and Predecki, P.K, Powder Diffraction, 6, (1), 1991 pp 16.Google Scholar
14. Aqua, Acta Cryst. (20) pp 560, 1966.Google Scholar
15. Rao, and Raman, , Zeit., Meatllkunde, B. D., 54, 1963 pp 658.Google Scholar
16. Anantharaman, T. R. Christian, J.D., Acta., Cryst. (9), 479. 1956.Google Scholar
17. Stokes, A.R., Proc. Phys. Soc, 61 pp 382 (1948).Google Scholar
18. Schwartz, L.H. and Cohen, J. B., ‘ Diffraction from Metals' , Academic Press, 1977 Google Scholar
19. Sheicner, W.N. Jenkins, R., Adv. X-Ray Analyses, 26, pp 41, 1983.Google Scholar
20. Marquardt, D. W. J. Soc. Indust. Appl. Math., 11, No.2 pp 431, 1963.Google Scholar
21. Langford, J.I., Appl Cryst, 11, pp (1978).Google Scholar
22. Cullity, B. D., Elements of X-Ray Diffraction , Addison Wesley, Reading, Ma, 2nd. ed. 1978.Google Scholar
23. Warren, B.E., X-ray Diffraction, Addison Wesley, Reading, Ma., 1969.Google Scholar
24. Delhez, R., Mettemeijer, E. J., J. Appl. Cryst., 9, pp 223 (1976).Google Scholar
25. Delhez, R., de Keijser, Th. H., Mettemeijer, E. J., Fresenious Zeitschr. Anal. Chem. 312, (1982) pp 1, and Th. H. de Keijser, Lanford, J. I., Mettemeijer, E. J., A. P. B. Vogels, J. Appl Cryst., 15, pp. 308 (1982).Google Scholar
26. Hartley, H. O., Technometrics., 3, pp 269–280 (1961).Google Scholar