Electron-optical studies of etch patterns on calcium fluoride
Abstract
Calcium-fluoride cleavages obtained from natural and synthetic crystals have been etched; the etch patterns, studied with an electron microscope by preparing single-stage carbon replicas shadowed with chromium. It is observed that no correlation of the etch patterns exist on the two sides of thin plates. The electron micrographs have revealed unusual round bottomed pits, and pits with slightly deformed structure; these have been attributed to the nature of imperfections at which they are nucleated. It is observed that pits divide, and thus pits are formed within the pits. By taking electron micrographs of the etch pattern on corresponding regions of matched pairs, it is shown that there is one-to-one correspondence, in number and position, of etch pits if the division of the etch pits is ignored; nevertheless correlation in the division of the etch pits is not observed. Thus it is conjectured that there exists a dislocation network in the body of calcium fluoride. The implications are discussed.
Artikel in diesem Heft
- A special case of two-dimensionally disordered crystals
- Die Kristallstruktur des Koenenits, eine Doppelschichtstruktur mit zwei inkommensurablen Teilgittern
- Zur Indizierung von Pulverdiagrammen tetragonaler und hexagonaler Substanzen
- Etch patterns on apophyllite basal cleavages
- Die Kristallstruktur von Li2(Si0,25Ge0,75)2O5
- The crystal structure of LiAlSi2O6-II (“β spodumene”)
- Phase solution of para-chlorophenol
- Crystal structure of an eighteen-layered polytype of cadmium iodide
- X-ray diffraction effects by non-ideal crystals of biotite, muscovite, montmorillonite, mixed-layer clays, graphite, and periclase*
- The crystal structure of alamosite, PbSiO31
- Sauerstoff als Koordinationszentrum in Kristallstrukturen
- Low-iron polymorphs in the pyrrhotite group
- Revised crystal structure of dehydrated Na-Type A zeolite
- Verfeinerung der Tl2O3-Struktur mittels Neutronenbeugung
- The location of hydrogen atoms in crystalline ionic hydrates
- Disorder phenomenon in cadmium iodide crystals
- Crystal structure of single-layer lizardite
- Proof that the pgg packing of ellipses has never the maximum density
- Weighting function in crystal-structure analysis*
- Tetrahedral metal groups in Fe2B and Mn4B structures
- Antisymmetrische OD-Strukturen
- Studies on etching of neutron-irradiated calcium fluoride single crystals
- Matrix methods in Fourier summations
- Electron-optical studies of etch patterns on calcium fluoride
- Structure of etch pattern at helical dislocations in NaCl single crystals
- Crystal structure of l(+)-cysteine hydrochloride monohydrate*
- Eighth International Congress of Crystallography
- Intercongress Meeting, 1968
Artikel in diesem Heft
- A special case of two-dimensionally disordered crystals
- Die Kristallstruktur des Koenenits, eine Doppelschichtstruktur mit zwei inkommensurablen Teilgittern
- Zur Indizierung von Pulverdiagrammen tetragonaler und hexagonaler Substanzen
- Etch patterns on apophyllite basal cleavages
- Die Kristallstruktur von Li2(Si0,25Ge0,75)2O5
- The crystal structure of LiAlSi2O6-II (“β spodumene”)
- Phase solution of para-chlorophenol
- Crystal structure of an eighteen-layered polytype of cadmium iodide
- X-ray diffraction effects by non-ideal crystals of biotite, muscovite, montmorillonite, mixed-layer clays, graphite, and periclase*
- The crystal structure of alamosite, PbSiO31
- Sauerstoff als Koordinationszentrum in Kristallstrukturen
- Low-iron polymorphs in the pyrrhotite group
- Revised crystal structure of dehydrated Na-Type A zeolite
- Verfeinerung der Tl2O3-Struktur mittels Neutronenbeugung
- The location of hydrogen atoms in crystalline ionic hydrates
- Disorder phenomenon in cadmium iodide crystals
- Crystal structure of single-layer lizardite
- Proof that the pgg packing of ellipses has never the maximum density
- Weighting function in crystal-structure analysis*
- Tetrahedral metal groups in Fe2B and Mn4B structures
- Antisymmetrische OD-Strukturen
- Studies on etching of neutron-irradiated calcium fluoride single crystals
- Matrix methods in Fourier summations
- Electron-optical studies of etch patterns on calcium fluoride
- Structure of etch pattern at helical dislocations in NaCl single crystals
- Crystal structure of l(+)-cysteine hydrochloride monohydrate*
- Eighth International Congress of Crystallography
- Intercongress Meeting, 1968
