Electronic and vibrational properties of pure MnPS3 crystal: Theoretical and experimental investigation

A systematic study of the electronic and vibrational properties of the MnPS3 single crystal within the DFT methodology applying the LDA and the GGA-D approximations is presented. Using the quantum chemical approach the energy band structure was calculated and comparatively analyzed. To obtain electronic parameters closer to experimental results the Hubbard correction (DFT-D + U) was added. The U parameter equal to 2.5 eV was applied for d-orbital of Mn atoms in the antiferromagnetic phase of the MnPS3 crystal essentially improving calculation results. The same method was used for calculations of phonon frequencies. The Raman spectra for the MnPS3 single crystal were measured in various scattering geometries at room and low temperature (5 and 90 K). A symmetry analysis and identification of vibration modes were also performed. Calculated electronic and lattice properties exhibit good qualitative and satisfactory quantitative agreement with experimental data.