Top-seeded solution growth and characterization of a Bi2Mo2.66W0.34O12 single crystal†
Abstract
Single crystals of Bi2Mo2.66W0.34O12 with dimensions up to 70 mm × 55 mm × 45 mm were successfully grown using a top-seeded solution growth (TSSG) method with a MoO3–WO3 mixture as a flux. The material crystallizes in centrosymmetric space group P21/c (no. 14), with unit cell parameters of a = 7.7212(8) Å, b = 11.4938(12) Å, c = 11.9970(12) Å, and β = 115.5070(10)°. The as-grown crystals exhibit {100}, {010}, {011}, {110}, {021}, {012}, {120}, {−111}, {−102}, and {1−1−2} facets, which are in good agreement with the predicted growth morphology based on the Bravais–Friedel and Donnay–Harker (BFDH) method. High-resolution X-ray diffraction (HRXRD) measurement on the (040)-faced plate shows that the full-width at half-maximum (FWHM) of the rocking curve is 54′′, which indicates high crystal quality. Our measurements show that it melts congruently and exhibits a wide transmission range from 475 nm to 5200 nm. It is worth noting that Bi2Mo2.66W0.34O12 has a large birefringence (Δn = 0.24 at 480 nm), indicating that the crystal can be a promising polarizing optical material.