ALLENEIDE PATTERNS

Structures with the 4- allene-ide anion would include a 4+ cation, tetragonal phase in P4-bar analogous to the calcium carbide structure containing a 2- acetylide anion & a 2+ calcium cation. A phase like titanium tri-carbide or other titanium (Group 4) tri-carbides…or a di-alkaline earth allene-ide in I4-bar for example, if such a structure is possible. The body centered tetragonal phase in I4-bar would be 2 alkaline earth cations to one allene-ide, with the allene-ide ion centered at (1/2, 1/2, 0) and the 2 alkaline earth cations at (0, 0, 0) & (1/2, 1/2, 1/2)…MJB