Structure, optical and phonon properties of bulk and nanocrystalline Al2−xScx(WO4)3 solid solutions doped with Cr3+

• Nanosized Al2−xScx(WO4)3 solid solutions were synthesized by co-precipitation method.
• Al2−xScx(WO4)3 single crystals were grown by the flux method.
• Raman and IR spectra show “two mode” behavior.
• Chromium ions occupy two sites of weak and strong crystal field strength.

Pure and Cr3+ doped nanosized Al2−xScx(WO4)3 solid solutions were prepared by co-precipitation method as well as Al2−xScx(WO4)3 single crystals were grown by high-temperature flux method. The obtained samples were characterized by X-ray, Raman, IR, absorption and luminescence methods. Single crystal X-ray diffraction showed that AlSc(WO4)3 is orthorhombic at room temperature with space group Pnca and trivalent cations are statistically distributed. Raman and IR studies showed that Al2−xScx(WO4)3 solid solutions show “two mode” behavior. They also showed that vibrational properties of nanosized samples have been weakly modified in comparison with the bulk materials. The luminescence and absorption spectra revealed that chromium ions occupy two sites of weak and strong crystal field strength.