Vemeuil method

Thermal stability is important in this method because the high temperatures reached may be sufficient to cause decomposition of the material. The Vemeuil Method of crystal growth is not generally applicable to all types of crystals. There are serious deficiencies in the method. For example, there is a large temperature drop of hundreds of degrees over a few millimeters within the crystal. This causes a large difference in thermal expansion within a limited space, and consequent... 

Figure 3.6 Methods for crystal growth from melt (a) Czochralski method (b) Kyropoulos method (c) Bridgman-Stockbarger method and (d) Vemeuil method.

Czrochralski growth equipment have made the Vemeuil method nearly obsolete. 

Figure 6-14. Boules of rare earth oxides grown by the conventional Vemeuil method. (Reproduced with permission from ref 103. Copyright 1966 Elsevier LTD.)...

Scandium oxide single crystals can be synthesized in only H2 atmosphere by the Vemeuil method [107]. The linear growth rate was about 8 mm h and the size of the obtained crystal has 45 mm length and 4 mm diameter. Pycnometric density of the obtained SC2O3 single crystal was 3.91 g-cm", Mohse hardness was 6.5, and refractive index was 1.91. 

Figure 36 Schematic of the Bridgeman crystal growth method (a). Vemeuil crystal growth method (b)...

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