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.

单斜晶系铕钼酸微晶（α-Eu2(MoO4)3）经固相合成法制备，合成温度为753-1273 K，持续时间为300小时。采用Rietveld方法对α-Eu2(MoO4)3的晶体结构进行了精修，发现其属于C2/c空间群，晶胞参数为a = 7.5576(1)、b = 11.4709(2)、c = 11.5158(2) Å，以及β = 109.278(1)°（RB = 3.39%）。在α-Eu2(MoO4)3粉末样品的拉曼光谱中观测到约40条狭窄的拉曼线。在355 nm和457.9 nm的激发下，α-Eu2(MoO4)3的发光光谱揭示了电偶极跃迁5D0 → 7F2的占主导地位，并在5D0 → 7F0和5D1 → 7F0跃迁处出现了极窄的谱线。