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Crystal Structure Descriptions, 2
In this appendix, most of the crystal structure types introduced in the
main text are formally described by means of their chemical formulas, Struk-
turBericht symbols, space groups, lattice parameters, special atom positions,
etc. In addition, examples of actual compounds with these structures are given,
along with their lattice parameters. All lattice parameters are stated in nm.
Structure types are listed in the order in which they appear in the text, and
are sequentially numbered. Most of the structural data in this appendix was
extracted from the following sources:
Pearson’s Handbook Desk Edition
, ASM International, Materials
Park, OH (1997);
, John Wiley, New York (1963);
C.S. Hurlbut and C. Klein,
Manual of Mineralogy, 9th Edition
, John Wiley
and Sons, New York (1977).
When consulting the tables on the following pages, one must be aware of
the fact that many compounds can have multiple crystal structures; it is always
a good idea to consult the original sources listed above (and others) to verify
that the correct structure is obtained. In particular, the examples of structures
of a given structure type will often include metastable structures, or high tem-
perature/high pressure phases; we refer the reader to the original sources for
those details. Furthermore, atom coordinates provided in this appendix have
been used with the sole purpose of creating structure visualizations; this means
that sites with partial occupancy will show up in a structure drawing as fully
occupied sites. The reader who wishes to compute x-ray powder patterns for
any of these structures should consult the original citations to make sure that
all site occupancies are properly accounted for.
The compound names for intermetallics are listed in the same convention
as in Pearson’s lists, namely an alphabetical ranking of all the elements in
the compound, except for the prototype chemical formulas, for which we fol-
low the list by J. Lima de Faria (J. Lima de Faria,
, Chapter 1 in
Intermetallic Compounds, Vol. 3
, edited by J.H.
Westbrook and R.L. Fleischer, John Wiley and Sons, New York (2002)). For
is the prototype for the
structure, which has Mg
as example compounds; note that the elements are listed alphabetically,
so that the
compound is sometimes written as
. The only exception
will be when the conventional prototype name is not in alphabetical order, for
instance ZnS, in which case we do not change the order to SZn.
The present version of this structures appendix was completed on June 16,
2013; updates containing corrections will be posted as needed.