Samarium(III) fluoride
Samarium fluoride is a slightly hygroscopic solid fluoride. Conditions/substances to avoid are: open flame, moisture, strong acids.
Preparation
Samarium fluoride can be obtained by reacting SmCl3 or Sm23 with 40% hydrofluoric acid:
Samarium fluoride can also be produced by hydrothermal reaction of samarium nitrate and sodium fluroborate at 200 °C.
Properties
Chemical
Samarium fluoride reacts with some reducing agents at high temperatures to obtain samarium(II) fluoride:
Physical
At room temperature, samarium fluoride has orthorhombic structure with space group Pnma – β-YF3 type with lattice constants a = 666,9 pm, b = 705,9 pm, c = 440,5 pm. Above 495 °C, it has the rhombohedral LaF3 structure – with lattice constants a = 707, c = 724 pm.