Unit cell containing 31 nitride ions (red) and 48 calcium ions (white). Each nitride is surrounded by six calcium, and each calcium by four nitride ions.
α-Calcium nitride adopts an anti-bixbyite structure, similar to Mn2O3, except that the positions of the ions are reversed: calcium (Ca2+) take the oxide (O2−) positions and nitride ions (N3−) the manganese (Mn3+). In this structure, Ca2+ occupies tetrahedral sites, and the nitride centres occupy two different types of octahedral sites.[2]
Synthesis and reactions
Calcium nitride is formed along with the oxide, CaO, when calcium burns in air. It can be produced by direct reaction of the elements:[3]
^ P. Ehrlich “Calcium, Strontium, Barium Nitrides Ca3N2, Sr3N2, Ba3N2” in Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 940-1.
^Heyns, A. (1998). "The Vibrational Spectra and Decomposition of α-Calcium Nitride (α-Ca3N2) and Magnesium Nitride (Mg3N2)". Journal of Solid State Chemistry. 137 (1): 33–41. Bibcode:1998JSSCh.137...33H. doi:10.1006/jssc.1997.7672.