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REFERENCES
1 Klein, C. and Dutrow, B. (2007). Manual of Mineral Science (Manual of Mineralogy), 23e. New York: Wiley 704 pp.
2 Pauling, L. (1929). The principles determining the structure of complex ionic structures. Journal American Chemical Society 51: 1010–1026.
3 Railsback, L.B. (2003). An earth scientist's periodic table of the elements and their ions. Geology 31: 737–740.
4 Wenk, H.R. and Bulakh, A. (2004). Minerals: Their Constitution and Origin, 3e. Cambridge, UK: Cambridge University Press 646 pp.
5 Wenk, H.R. and Bulakh, A. (2016). Minerals: Their Constitution and Origin, 3e. Cambridge, UK: Cambridge University Press 621 pp.
Chapter 3 Atomic substitution, phase diagrams, and isotopes
1 ssss1
2 ssss1
3 ssss1
3.1 ATOMIC (IONIC) SUBSTITUTION
ionic substitution24
Substitution is favored for ions of similar ionic radius. In general, cation substitution at surface temperatures and pressures is limited when the larger cation radii exceed the smaller by 10–15% and becomes negligible for differences greater than 30%. Such ions are “too big” or “too small” to easily substitute for one another (ssss1a), while ions of similar size are “just right.” Substitution of ions of significantly different radii distorts coordination polyhedra and decreases the stability of crystals. However, at higher temperatures, where the crystal structure is expanded, ions with larger differences in radius may more easily substitute for one another.