Polycrystalline A3 and

A slight excess of TiX3 and VX3 is used for the synthesis. The following quantities are suitable for ampules of 30-cm length and 2-cm diameter  

The filled ampules are evacuated to a pressure of 10 3 torr. As described for the synthesis of TiBr3 (previous section) the lower part of the ampule is cooled while sealing quickly with a very hot flame. The sealed ampule is placed in a slightly inclined ( 15 °C) furnace and heated at a rate of 100°Ch-1 to the reaction temperature (Table I). After the reaction time listed in Table I the heating power is switched off, and the system is left to cool down to room temperature. 

All the products are homogeneous and polycrystalline. Single-crystalline domains of several hundered cubic millimeters are not uncommon for the chlorides. Some further properties are listed in Table I. 

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