Question

Iron titanate, FeTiO3, forms in the ilmenite crystal structure that consists of an HCP arrangement of 02- ions. (a) Which type of interstitial site will the Fe2+ ions occupy? sites (b) Which type of interstitial site will the Ti4+ ions occupy? sites (c) What fraction of the total tetrahedral sites will be occupied? (In decimal form to two places to the right of the decimal) (d) What fraction of the total octahedral sites will be occupied? (In decimal form to two places to the right of the decimal)

Answer 1

Let us solve this problem step by step- Step 1: Using the radius of ions from table, we have a) Rrezt = 0.072 nm R2 = .140nm 40 nm Ratio = هکده و 0.077 0.140 octahedral sites Here Fe2+ ions will occupy because ratio ist between • 414 to 732 1. b) RT.4+ = .068 nm Ro- = -140 nm Ratio = 0.068 140 .48 out Tit ion will occupy octahedral site Reason: I 0.414 <.486 .732

o zero because fraction of tetrahedral both have same sites. site occupt 9n Fetion 30 ions available and 3 octahedral sites are Feet & one Tiut s one will remain octahedral site octahedral site uno ccupied so, fraction octahedral sites will occupied