Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-14T06:10:37.876Z Has data issue: false hasContentIssue false

Chemical reasonableness in Rietveld analysis: Inorganics

Published online by Cambridge University Press:  01 March 2012

James A. Kaduk
Affiliation:
INEOS Technologies, P.O. Box 3011, MC F-9, Naperville, Illinois 60563

Abstract

Besides statistical and graphical measures, many structural features can be used to assess the quality of a Rietveld refinement. These include the metric symmetry of the lattice (which can assist in determining the true symmetry and in identifying isostructural compounds), bond distances and angles (which should fall within normal ranges), displacement coefficients, refined stoichiometry, the absolute values of the standard uncertainties of the fractional coordinates, the hydrogen bonding pattern, the presence of approximate symmetry, the presence of unindexed peaks in the pattern, and whether the refinement converges at all. Chemical knowledge can be built into a Rietveld refinement though the use of restraints and rigid bodies. A knowledge of chemical reasonableness proved important in refining the correct structures of [Fe(H2O)6](BF4)2, (Ba1.5Sr0.5)TiO4, and (Ba1.25Sr0.75)TiO4.

Type
Crystallography Education
Copyright
Copyright © Cambridge University Press 2007

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

Allen, F. H. (2002). “The Cambridge Structural Database: a quarter of million crystal structures and rising, ” Acta Crystallogr.ASBSDK10.1107/S0108768102003890 58, 380388.CrossRefGoogle ScholarPubMed
Bergerhoff, G. and Brandenburg, K. (1999). “Typical interatomic distances; inorganic compounds, ” in International Tables for Crystallography, Volume C: Mathematical, Physical, and Chemical Tables, 2nd ed., edited by Prince, E. and Wilson, A. J. C. (Springer, New York), pp. 770781.Google Scholar
Bland, J. A. (1961). “The crystal structure of barium orthotitanate, Ba2TiO4, ” Acta Crystallogr.ACCRA910.1107/S0365110X61002527 14, 875881.CrossRefGoogle Scholar
Boultif, A. and Louër, D. (1991). “Indexing of powder diffraction patterns for low symmetry lattices by the successive dichotomy method, ” J. Appl. Crystallogr.JACGAR10.1107/S0021889891006441 24, 987993.Google Scholar
Brese, N. and O’Keeffe, M. (1991). “Bond valence parameters for solids, ” Acta Crystallogr.ASBSDK10.1107/S0108768190011041 47, 192197.CrossRefGoogle Scholar
Brown, I. D. (1996). “VALENCE: a program for calculating bond valences, ” J. Appl. Crystallogr.JACGAR10.1107/S002188989600163X 29, 479480.CrossRefGoogle Scholar
Brown, I. D. (2002). The Chemical Bond in Inorganic Chemistry: The Bond Valence Model (IUCr Monographs on Crystallography 12) (Oxford University Press, New York).Google Scholar
Brown, I. D. and Altermatt, D. (1985). “Bond-valence parameters obtained from a systematic analysis of the Inorganic Crystal Structure Database, ” Acta Crystallogr.ASBSDK10.1107/S0108768185002063 41, 244247.Google Scholar
Ghosh, M. and Ray, S. (1981). “Twinning, disorder and phase transition in ferrous perchlorate, ” Z. Kristallogr.ZEKRDZ 155, 129137.Google Scholar
Günter, J. R. and Jameson, G. B. (1984). “Orthorhombic barium orthotitante, α′-Ba2TiO4, ” Acta Crystallogr.ACSEBH 40, 207210.Google Scholar
Hellenbrandt, M. (2004). “The Inorganic Crystal Structure Database (ICSD)—present and future, ” Crystallogr. Rev.CRRVEN10.1080/08893110410001664882 10, 1722.Google Scholar
Helliwell, J. R., Strickland, P. R., and McMahon, B. (2006). “The role of quality in providing seamless access to information and data in e-science; the experience gained in crystallography, ” Inf. Services Use 26, 4555.Google Scholar
Kaduk, J. A. (2007). “Chemical reasonableness in Rietveld analysis: organics, ” Powder Diffr.PODIE210.1154/1.2464129 22, 7482.Google Scholar
Kwestroo, W. and Paping, H. A. M. (1959). “The systems BaO–SrO–TiO2, BaO–CaO–TiO2, and SrOCaO–TiO2, ” J. Am. Ceram. Soc.JACTAW10.1111/j.1151-2916.1959.tb12957.x 42, 292299.Google Scholar
Larson, A. C. and Von Dreele, R. B. (2000). General Structure Analysis System (GSAS) (Report LAUR 86-748), Los Alamos, New Mexico: Los Alamos National Laboratory.Google Scholar
Lines, M. E. and Glass, A. M. (1997). Principles and Applications of Ferroelectrics and Related Materials (Oxford University Press, New York).Google Scholar
Lukaszewicz, K. (1959). “Crystal structures of α-(SrO)2(TiO) and (SrO)3(TiO2)2, ” Rocz. Chem.ROCHAC 33, 239242.Google Scholar
McCusker, L. B., Von Dreele, R. B., Cox, D. E., Louër, D., and Scardi, P. (1999). “Rietveld refinement guidelines, ” J. Appl. Crystallogr.JACGAR10.1107/S0021889898009856 32, 3650.Google Scholar
Mighell, A. D. and Himes, V. L. (1986). “Compound identification and characterization using lattice-formula matching techniques, ” Acta Crystallogr.ACACEQ10.1107/S0108767386099804 42, 101105.CrossRefGoogle Scholar
Mighell, A. D. and Rogers, J. R. (1980). “Lattice symmetry determination, ” Acta Crystallogr.ACACBN10.1107/S0567739480000617 36, 321326.Google Scholar
Ostrovskaya, T. V., Amirova, S. A., and Startseva, N. V. (1967). “Chemical transformations of iron, cobalt, and nickel tetrafluoroborates, ” Zh. Neorg. Khim.ZNOKAQ 12, 23272330.Google Scholar
Ruddlesden, S. N. and Popper, P. (1957). “New compounds of the K2NiF4-type, ” Acta Crystallogr.ACCRA910.1107/S0365110X57001929 10, 538539.CrossRefGoogle Scholar
Russell, D. R. and Sharp, D. W. A. (1961). “The lattice constants of some metal-fluoroborate hexahydrates, ” Acta Crystallogr.ACCRA910.1107/S0365110X61001133 14, 330.Google Scholar
Shannon, R. D. and Prewitt, C. T. (1969). “Effective ionic radii in oxides and fluorides, ” Acta Crystallogr.ACBCAR10.1107/S0567740869003220 25, 925946.Google Scholar
Shannon, R. D. and Prewitt, C. T. (1970). “Revised values of effective ionic radii, ” Acta Crystallogr.ACBCAR10.1107/S0567740870003576 26, 10461048.CrossRefGoogle Scholar
Sidey, V. (2006). “Accurate bond-valence parameters for the Bi3+/Br ion pair, ” Acta Crystallogr.ASBSDK10.1107/S0108768106020295 62, 949951.Google Scholar
Smith, G. S. and Snyder, R. L. (1979). “F N: A criterion for rating powder diffraction patterns and evaluating the reliability of powder-pattern indexing, ” J. Appl. Crystallogr.JACGAR10.1107/S002188987901178X 12, 6065.CrossRefGoogle Scholar
Spek, A. L. (2003). “Single-crystal structure validation with the program PLATON, ” J. Appl. Crystallogr.JACGAR10.1107/S0021889802022112 36, 713.Google Scholar
Srivastava, R. C., Klooster, W. T., and Koetzle, T. F. (1999). “Neutron structures of ammonium fluoroberyllate, ” Acta Crystallogr.ASBSDK10.1107/S010876819800737X 55, 1723.Google Scholar
Stalick, J. K. and Mighell, A. D. (1986). “Crystal Data, Version 1.0, Database Specifications, ” NBS Technical Note 1229.Google Scholar
Toby, B. H. (2006). “R factors in Rietveld analysis: How good is good enough?” Powder Diffr.PODIE210.1154/1.2179804 21, 6770.CrossRefGoogle Scholar
Toby, B. H. (2007). “Graphical appraisal of the quality of a Rietveld refinement” (in preparation).Google Scholar
Villars, P., Onodera, N., and Iwata, S. (1998). “The Linus Pauling File (LPF) and its application to materials design, ” J. Alloys Compd.JALCEU10.1016/S0925-8388(98)00605-7 279, 17.CrossRefGoogle Scholar
Visser, J. W. (1969). “Fully automatic program for finding the unit cell from powder data, ” J. Appl. Crystallogr.JACGAR 2, 7895.Google Scholar
West, C. D. (1935). “Crystal structures of hydrated compounds. II. Structure type Mg(ClO4)2(H2O)6, ” Z. Kristallogr.ZEKRDZ 91, 480493.Google Scholar
White, P. S., Rodgers, J. R., and Le Page, Y. (2002). “CRYSTMET: a database of the structures and powder patterns of metals and intermetallics, ” Acta Crystallogr.ASBSDK10.1107/S0108768102002902 58, 343348.CrossRefGoogle ScholarPubMed
Wong-Ng, W., Kaduk, J. A., Kaiser, D. B., and Frank, J. (2007). “Crystallography and crystal chemistry of (Ba1−xSrx)2TiO4” (unpublished results).Google Scholar
Wu, K. K. and Brown, I. D. (1973). “The crystal structure of β-barium orthotitanate, β-Ba2TiO4, and the bond strength-bond length curve of Ti–O, ” Acta Crystallogr.ACBCAR10.1107/S0567740873005959 29, 20092012.CrossRefGoogle Scholar