Нитрид Кальций

Описание

Calcium nitride has the formula of Ca3N2 and the molecular weight of grams per mole. It can be prepared by the reactionofCametal inapure streamof nitrogen gas:
3Ca + 2N2 ? Ca3N2
A second method is the decomposition of an amide:
3Ca(NH2)2 + heat ? Ca3N2 + 4NH3
This must be accomplished in an inert atmosphere (not nitrogen gas). It is a reddish-brown powder. Its CAS number is 12013-82-0 and its density is 2.76 g/ cm³. It melts at 1195 °C (2183 F).α-Calcium nitride is the commonly encountered form. It has an antibixbyite structure similar to Mn2O3, except that the positions of the ions are reversed: calcium (Ca²⁺) ions take the oxide (O^2-) positions and nitride ions (N^3-) that of the manganese (Mn³⁺). If Ca metal is burned in air, it forms the oxide, CaO, and the nitride, Ca3N2. The latter reacts with atmospheric moisture to produce the hydroxide of calcium and ammonia:
Ca3N2 + 6H2O ? 3Ca(OH)2 + 2NH3

Химические свойства

12mm pieces and smaller, -200 mesh 99% pure; brown crystal(s); hex: a=0.3533nm, c=0.411 nm; cub: a=1.138 nm [CIC73] [CER91]

Использование

Recent advances in the utilization of single crystals for a wide variety of purposes, especially in various electronic surveillance and detection applications, has generated considerable research in the development of improved techniques for growing single crystalline materials. A problem has arisen, however, in that many of the methods relied upon heretofore fail to growcrystals having a reproducibly high quality. Calcium nitride as a high temperature solvent has been used in the recrystallization of refractory aluminum nitride, that is growing single crystals of aluminum nitride from a molten solution containing the refractory material as the solute, and calcium nitride as the solvent. Crystallization is accomplished by the precipitation or crystallization of the solute, the solute being the desired crystal, from the molten solution.