FIRST-PRINCIPLES LCAO CALCULATIONS ON 5D TRANSITION METAL OXIDES: ELECTRONIC AND PHONON PROPERTIES

ABSTRACT

First-principles quantum chemistry calculations within the periodic linear combination of atomic orbitals (LCAO) formalism have been used to probe electronic and phonon properties of crystalline 5d transition metal oxides ReO₃, ZnWO₄ and CaWO₄. The obtained equilibrium crystal structure is in good agreement with known crystallographic data. Rhenium trioxide is correctly predicted to be a metal, whereas both tungstates—a wide gap insulating compounds. The phonon frequencies, calculated by the frozen phonon method, agree rather well with those obtained by infrared and Raman spectroscopies.

Keywords:

• Quantum chemistry
• crystal structure
• electronic structure
• phonons
• oxides

ACKNOWLEDGMENTS

R.A.E. and M.L. wish to thank Dr. A. Togo for the help with the fropho code. The authors are grateful for the support of the Russian Basic Research Foundation (grant 08-03-00438-a), Latvian Government Research Grant No. 09.1211 and Latvian National Research Program in Materials Science.