Hostname: page-component-7dd5485656-zlgnt Total loading time: 0 Render date: 2025-10-29T23:31:55.956Z Has data issue: false hasContentIssue false
  • English
  • Français

Chemical accuracy and precision in Rietveld analysis: The crystal structure of cobalt(II) acetate tetrahydrate

Published online by Cambridge University Press:  10 January 2013

James A. Kaduk  and
Walt Partenheimer
James A. Kaduk
Affiliation:
Amoco Corporation, P.O. Box 3011, MC F-9, Naperville, Illinois 60566
Walt Partenheimer
Affiliation:
Amoco Corporation, P.O. Box 3011, MC F-9, Naperville, Illinois 60566
Get access Rights & Permissions [Opens in a new window]

Abstract

The crystal structure of cobalt(II) acetate tetrahydrate, Co(C2H3O2)·4H2O, has been refined using single-crystal, laboratory powder, and synchrotron powder diffraction data, both individually and in various combinations. The compound crystallizes in the monoclinic space group P21/c, with a=4.80688(3), b=11.92012(7), c=8.45992(5) Å, β=94.3416(4)° at 27 °C, and Z=2. The crystal structure consists of discrete centrosymmetric trans-Co(C2H3O2)(H2O)4 complexes, linked by a three-dimensional network of hydrogen bonds. Each complex participates in 14 hydrogen bonds, 12 intermolecular, and 2 intramolecular. Compared to the single-crystal refinement, refinement of laboratory powder data yielded an average difference in bond distances of 0.02 Å, in bond angles of 3°, and in root mean square atomic displacements of 0.07 Å. The standard uncertainties of the bond distances were 0.01 Å, compared to the 0.001–0.002 Å in the single-crystal refinement. Refinement of the synchrotron powder data yielded improved accuracy and precision. It proved impossible to locate or refine hydrogen positions using a single-powder dataset, but the hydrogens could be refined using rigid groups in a joint refinement of the two powder datasets. Even from powder refinements, it is possible to obtain suitable accuracy and precision to distinguish C–O and C=O bonds, and to examine details of chemical bonding.

Information

Type
Research Article
Information
Powder Diffraction , Volume 12 , Issue 1 , March 1997 , pp. 27 - 39
Copyright
Copyright © Cambridge University Press 1997

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.)

Article purchase

Temporarily unavailable

References

Allen, F. H., Davies, J. E., Galloy, J. J., Johnson, O., Kennard, O., Macrae, C. F., Mitchell, E. M., Mitchell, G. F., Smith, J. M., and Watson, D. G., (1991). “The Development of Versions 3 and 4 of the Cambridge Structural Database System,” J. Chem. Info. Comp. Sci. 31, 187.CrossRefGoogle Scholar
Bish, D. L., and Howard, S. A. (1988). “Quantitative Phase Analysis Using the Rietveld Method,” J. Appl. Cryst. 21, 86–91.CrossRefGoogle Scholar
Hill, R. J. (1992). “International Union of Crystallography Commission on Powder Diffraction Rietveld Round Robin. I. Analysis of Standard X-ray and Neutron Data for PbSO4,” J. Appl. Cryst. 25, 589–610.CrossRefGoogle Scholar
Hill, R. J., and Cranswick, L. M. D. (1994). “International Union of Crystallography Commission on Powder Diffraction Rietveld Round Robin. II. Analysis of Monoclinic ZrO2,” J. Appl. Cryst. 27, 802–844.CrossRefGoogle Scholar
Hill, R. J., and Howard, C. J. (1987). “Quantitative Phase Analysis from Neutron Powder Diffraction Data Using the Rietveld Method,” J. Appl. Cryst. 20, 467–474.CrossRefGoogle Scholar
Kaduk, J. A. (1996). “Chemical Accuracy and Precision in Structure Refinement from Powder Data,” presented at the 45th Annual Denver X-ray Conference, August 1996, and submitted to Adv. X-Ray Anal.Google Scholar
Larson, A. C., and Von Dreele, R. B. (1994). GSAS, The General Structure Analysis System, Los Alamos National Laboratory, November 1994.Google Scholar
Lippincott, E. R., and Schroeder, R. (1955). “One-Dimensional Model of the Hydrogen Bond,” J. Chem. Phys. 23(6), 1099–1106.CrossRefGoogle Scholar
Partenheimer, W., and Kaduk, J. A. “The Importance of Hydrogen Bonding in the Precipitation of Metals by Aromatic Acids in Acetic Acid/Water Mixtures during the Autoxidation of Polymethylbenzenes,” submitted to J. Mol. Catalysis.Google Scholar
Powder Diffraction File entry 25-372 (1995). “Cobalt acetate hydrate,” International Centre for Diffraction Data.Google Scholar
Powder Diffraction File entry 45-1708 (1995). “Bis(dihydrogentrimellitato)tetraaquacobalt dihydrate,” International Centre for Diffraction Data.Google Scholar
Rietveld, H. M. (1969). “A Profile Refinement Method for Nuclear and Magnetic Structures,” J. Appl. Cryst. 2, 65–71.CrossRefGoogle Scholar
SHELXTL Plus (1988). Version 3.4, Nicolet Instrument Corporation.Google Scholar
Stalick, J. K. (1992). “Quantitative Phase Analysis with the Rietveld Method,” NIST Special Publication 846, 34–37.Google Scholar
van Niekerk, J. N., and Schoening, F. R. L. (1953). “The Crystal Structures of Nickel Acetate, Ni(CH3COO)2·4H2O, and Cobalt Acetate, Co(CH3COO)2·4H2O,” Acta Cryst. 6, 609–612; CSD Refcode COAQAC.Google Scholar