Synthesis and Spectroscopic Properties of Monoclinic α‑Eu₂(MoO₄)₃

The microcrystals of monoclinic europium molybdate, α-Eu2(MoO4)3, have been fabricated by solid-state synthesis at T = 753–1273 K for 300 h. The crystal structure of α-Eu2(MoO4)3 has been refined by the Rietveld method and was found to belong to the space group C2/c with unit cell parameters a = 7.5576(1), b = 11.4709(2), c = 11.5158(2) Å, and β = 109.278(1)° (RB = 3.39%). About 40 narrow Raman lines have been observed in the Raman spectrum of the α-Eu2(MoO4)3 powder sample. The luminescence spectra of α-Eu2(MoO4)3 under excitation at 355 and 457.9 nm reveal domination of induced electric dipole transition 5D0 → 7F2 and the presence of ultranarrow lines at 5D0 → 7F0 and 5D1 → 7F0 transitions.