Neodymium(III) iodide is an inorganic salt of iodine and neodymium with the formula NdI3.[3] Neodymium uses the +3 oxidation state in the compound. The anhydrous compound[2] is a green powdery[2] solid at room temperature.
Preparation
Heating neodymium and iodine in an inert atmosphere produces this salt:[citation needed]
The anhydrate can then be obtained by heating the nonahydrate with ammonium iodide:[4]
NdI3 • 9 H2O + nNH4I → NdI3 + nNH3 + nHI + 9H2O
Physical properties
Neodymium(III) iodide forms green, water-soluble hygroscopiccrystals. It has a melting point of 784°C. It forms a nonahydrate crystal NdI3.9H2O – belongs to the orthorhombic crystal system, space groupPmmn, lattice constants a = 1.16604 nm, b = 0.80103 nm, c = 0.89702 nm, Z = 4.[5]
Other compounds
NdI3 also forms some compounds with N2H4, such as NdI3·3N2H4·2H2O which is a dark green crystal, soluble in methanol and ethanol and insoluble in water, benzene and toluene, d20°C = 3.42 g/cm³.[6]
NdI3 also forms some compounds with urea, such as NdI3 5CO(NH2)2 which is a lavender color crystal.[7]
NdI3 also forms some compounds with thiourea, such as NdI3·2CS(NH2)2·9H2O which is a pale pink crystal.[8]