https://dictionary.iucr.org/crystal: historical, reciprocal and direct space definitions. Expert discussions also raised the issue of different dimensionality crystals, quasicrystals and so on.
https://en.wikipedia.org/wiki/Crystal: information as above, as well as history of the term, some discussion of various types of crystal including quasicrystals and crystal defects.
Comments
The vast majority of crystal structures are formed of arrangements of atoms that are periodic in 3 dimensions (400,000 according to Wikipedia reference 20). Almost all measurements on samples are modelled assuming the sample is a single crystal.
General Concept Info
IRI: TBA
OWL type: TBA
Concept elucidation
A sample of a solid substance that has been well-described by using a crystalline model (see #5 ). No more than one crystalline model is required for modelling the measurements, so the sample is neither twinned nor a powder.
A material can only be known to be crystalline after measurements have been taken on it. For example, cut glass may appear the same as a naturally-occuring crystal, but is not crystalline. The canonical measurement technique is to illuminate a sample of the material with beams of electrons, X-rays, or neutrons, and if intensity is detected in specific directions the material is considered crystalline. If the intensities and positions of all of the spots thus detected from a sample can be modelled using a single crystalline model, the sample is considered to be a single crystal. A material would not itself be considered a "single crystal", as various samples of notionally the same material might not all be single crystals.
Knowledge domain resources
Related
https://dictionary.iucr.org/crystal: historical, reciprocal and direct space definitions. Expert discussions also raised the issue of different dimensionality crystals, quasicrystals and so on.
https://en.wikipedia.org/wiki/Crystal: information as above, as well as history of the term, some discussion of various types of crystal including quasicrystals and crystal defects.
Comments
The vast majority of crystal structures are formed of arrangements of atoms that are periodic in 3 dimensions (400,000 according to Wikipedia reference 20). Almost all measurements on samples are modelled assuming the sample is a single crystal.
General Concept Info
IRI: TBA
OWL type: TBA
Concept elucidation
A sample of a solid substance that has been well-described by using a crystalline model (see #5 ). No more than one crystalline model is required for modelling the measurements, so the sample is neither twinned nor a powder.
Preferred label
"single crystal"
Alternate labels
"crystal", "three-dimensional crystal", "periodic crystal"
Discussion
A material can only be known to be crystalline after measurements have been taken on it. For example, cut glass may appear the same as a naturally-occuring crystal, but is not crystalline. The canonical measurement technique is to illuminate a sample of the material with beams of electrons, X-rays, or neutrons, and if intensity is detected in specific directions the material is considered crystalline. If the intensities and positions of all of the spots thus detected from a sample can be modelled using a single crystalline model, the sample is considered to be a single crystal. A material would not itself be considered a "single crystal", as various samples of notionally the same material might not all be single crystals.