What Is The Crystal Structure Of Niobium Iodide?

Niobium iodide can exist in several crystal structures depending on the synthesis method and conditions. The most common form is known as alpha-niobium iodide, which has a hexagonal close-packed lattice structure with space group P6/mmm and lattice parameters of a = b = 3.305 Å and c = 5.139 Å at room temperature. Each niobium atom is coordinated by six iodine atoms in a distorted octahedral arrangement, while each iodine atom is coordinated to three niobium atoms. Beta-niobium iodide also exists, which has a body-centered cubic lattice structure with space group Im-3m and lattice parameter of 6.734 Å.