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[求助] Microwave-assisted synthesis and optical property of CdMoO4

可以请哪位专业人士帮我翻译下这一段吗？感觉专业词汇很多诶
In lattice space, scheelite compounds (CaMoO4,CaWO4,SrMoO4,SrWO4, etc.) correspond to S4 symmetry. A group theoretical analysis of the scheelite structure yields 26 lattice modes at theG point of the Brillouin zone—3Ag+5Au+5Bg+3Bu
+5Eg+5Eu. The 13 g modes are Raman active, and the 13 u modes are infrared active(4Au and 4Eu), acoustic (1Au and 1Eu), and silent (3Bu). The Raman
active phonon modes can be classified into two types of vibrations,the internal and external modes (rotation and translation) with respect to (w.r.t.) the [MoO4]2 -tetrahedrons. Among them, seven modes are internal stretching vibrations of n1(Ag), n3(Bg), and n3(Eg),and bending of n2(Ag), n2(Bg), n4(Bg), and n4(Eg). The six remaining are external modes—three rotations, two translations, and an unidentified mode. The internal modes correspond to normal vibrations of the [MoO4]2- tetrahedrons, while the external modes involve motions of the metallic atoms (e.g. Ca, Sr, Ba, Cd, etc.) w.r.t.[MoO4]2-tetrahedrons [10–12,15,18–20]. It is expected that the frequencies and wavenumbers of the internal stretching modes are higher than those of the external ones, because the internal covalent
bonding within the [MoO4]2- tetrahedrons is stronger than the
external lattice binding. Fig. 3a shows the Raman spectra of CdMoO4
produced by the microwave radiation method under different
conditions. They show strong Raman peaks that indicate a strong
interaction between the ions, which mainly arise from the stretching
and bending vibrations of the shorter metal–oxygen bonds within
the anionic groups. All Raman spectra were identified as n1(Ag),n3(Bg), n3(Eg), n4(Eg,Bg), and n2(Ag,Bg) at 862, 820, 755, 396, and 309 cm-1
, respectively. Three rotation and two translation modes of [MoO4]2- units were detected at 280, 192, 153, 135, and 102 cm-1,respectively. These results are in accordance with those reported in the literature, although their wavenumber vibra-tion modes were not exactly the same values, due to the difference in geometries, particle sizes, and nature of the products

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