polytype

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polytype

(ˈpɒlɪˌtaɪp)
n
1. (Chemistry) crystallog a crystal occurring in more than one form
2. (Printing, Lithography & Bookbinding) printing a printing cast
vb (tr)
(Printing, Lithography & Bookbinding) printing to produce by use of a polytype
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References in periodicals archive ?
Morrison, "Polytypism and the vibrational properties of Pb[I.sub.2]," Physical Review B: Condensed Matter and Materials Physics, vol.
Hejny and T Armbruster, "Polytypism in xonotlite [Ca.sub.6][Si.sub.6][O.sub.17][(OH).sub.2]," Zeitschriftfur Kristallographie, vol.
(1992) Polytypism in donnayite (Na,TR)Sr(C[O.sub.3])[.sub.2]*[H.sub.2]O.
The redpoll finch complex (Ayes: Carduelinae: Carduelis flammea-hornemanni) provides an opportunity to examine the relationship between polytypism, gene flow, and phylogeographic structuring of genetic variation.
Graomys griseoflavus is another example where Rb translocations generate chromosomal polymorphism and polytypism. This distribution pattern of Rb variability was also observed in the phyllotine Eligmodontia puerulus, the oryzomyine Holochilus brasiliensis and the murine Mus musculus domesticus (Nachman, 1992; Pialek et al., 2005; Lanzone et al., 2011).
Bechstedt, "Polytypism of GaAs, InP, InAs, and InSb: an ab initio study, " Physical Review B, vol.
Korgel, "Wurtzite-Chalcopyrite polytypism in CuIn[S.sub.2] nanodisks," Chemistry of Materials, vol.
Polytypism describes the sequence of types I and II within the mica structure.
The remainder of this chapter describes numerous examples of chromosomal polytypism in several groups of rodents (Acomys, Gerbillus, Peromyscus, Proechimys, Rattus, Spalax, and Thomomys), bats (Rhogeesa), shrews (Sorex), and lizards (Gehyra, Phyllodactylus, and Sceloporus).
The discovery of polytypism, first in the kaolinite minerals (Hendricks, 1939) and later in micas (Heinrich and Levinson, 1955), and the following refinement of crystal structures in all groups of phyllosilicates and their polytypes was a result of a cooperation among physicists, crystallographers, chemists and mineralogists in later decades (see literature compiled by Konta, 2000).
The knowledge of the mineralogical and chemical composition of natural pyrophyllite material, and several observations recently made on the ground material (X-ray characteristics, surface area and dehydroxylation temperatures) have now made it easier to approach the structural alteration with a new look from a point of view of polytypism. In natural samples of clay minerals of the talc-pyrophyllite group one finds significant structure disorder (Wiewiora et al., 1993; Wiewiora and Hida, 1996).