Samarium(III) fluoride (SmF3) is a slightly hygroscopic solid fluoride. Conditions/substances to avoid are: open flame, moisture, strong acids.
Preparation
Samarium(III) fluoride can be obtained by reacting SmCl3 or Sm2(CO3)3 with 40% hydrofluoric acid:[1]
SmCl3 + 3 HF → SmF3↓ + 3 HCl
Sm2(CO3)3 + 6 HF → 2 SmF3 + 3 H2O + 3 CO2↑
Samarium(III) fluoride can also be produced by hydrothermal reaction of samarium nitrate and sodium fluroborate at 200 °C.[2]
Properties
Chemical
Samarium(III) fluoride reacts with some reducing agents at high temperatures to obtain samarium(II) fluoride:
Physical
At room temperature, samarium(III) fluoride has orthorhombic structure with space groupPnma – β-YF3 type with lattice constantsa = 666,9 pm, b = 705,9 pm, c = 440,5 pm. Above 495 °C, it has the rhombohedralLaF3 structure (space group P3cl) – with lattice constants a = 707, c = 724 pm.[3]