TERNARY METAL-RICH PHOSPHIDES - STRUCTURE, BONDING, AND SITE PREFERENCES IN ZRNBP AND HF1+XMO1-XP

Semiempirical electronic structure calculations are utilized to assess the bonding and metal atom arrangement in the recently discovered ternary phosphide ZrNbP, which adopts the Co2Si structure type. These same calculations reveal that ZrMoP should form in the Fe2P structure type due primarily to metal-metal interactions within each system. Related structural alternatives like the Cu2Sb-type and the Ni2In-type are also examined for their stability ranges as a function of valence electron concentration (vec). Synthesis and structural characterization of Hf1.06Mo0.94P by single-crystal X-ray diffraction are also reported and confirm the prediction of stability of the Fe2P structure type for this vee. Hf1.06Mo0.94P crystallizes in the space group P ($) over bar 62m (No. 189); a = 6.8954(4) Angstrom; c = 3.4164(4) Angstrom; Z = 3; R = 0.024; R(w) = 0.027 (1 greater than or equal to 3 sigma(I)).