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Raman spectra of oxyorthosilicate Lu2SiO5 have been computed in the framework of density functional theory with hybrid functionals using molecular orbitals approximation. Results are compared with existing experimental data. With general agreement with experiment, there are differences in some regions of wavenumbers. Analysis of vibrations has been performed using calculated eigenvectors and isotopic substitution method. Optimized crystal structure parameters are in excellent agreement with the experiment with maximum difference less than 2%. Obtained value of the band gap 6.43 eV is also in a good agreement with the literature data (6 eV).

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We report a theoretical approach to the investigation of the magnetic hyperfine interaction on the 51 V nucleus in Lu 2 V 2 O 7 with the view of understanding the orbital ordering pattern in this compound. First, we have evaluated the vanadium 3d 1 -level splitting ( ) under the crystal field with the D 3d -symmetry using the point charges approximation. Second, we have calculated the exchange interaction constant (J) using the ab initio approach. It is shown that the crystal field energy is much stronger than the exchange interaction one and hence the orbital liquid state cannot occur in Lu 2 V 2 O 7 . Finally we have analyzed the magnetic hyperfine field affecting the vanadium nucleus leaning upon these results.