Growth and Characterization of Tetraphenylphosphonium Bromide Crystal

Abstract

Multiple-phenyl phosphorous compounds are a group of chemical materials that have been used as reactants, pharmaceutical intermediates, extractants, and catalysts in organic synthetic reactions. However, the crystal growth of bulk crystals of multiple-phenyl phosphorous compounds, which may expand their applications in photonics technology, have been largely overlooked. In this article, the crystal growth of tetraphenylphosphonium bromide (TPPB) has been studied in organic solvents and water. The crystal structures and crystallization features are analyzed by X-ray diffraction data. By a slow temperature-lowering method, a single-crystal of TPPB (2H 2 O) with the size of 27 × 20 × 20 mm 3 has been obtained in water. The basic thermal and optical properties were characterized. We find that the TPPB (2H 2 O) crystal shows excellent transparent property in the near-IR region. Large Raman shifts and strong Raman scattering intensity indicate that TPPB is a potential candidate in Raman-scattering-based nonlinearity applications.

Room-Temperature Seeded Growth of Tetraphenylphosphonium Bromide Single-Crystalline Fibers

“…24 The structure of TppBr fibers is identical with that of its bulk crystal obtained by the spontaneous nucleation and growth in water solution (Figure 2a). 20 There are two molecules of crystal water in the lattice. The XRD spectrum of TppBr fibers without grinding shows that the strong diffractions come from (101), (103), and (100) crystal faces (see Figure 2b).…”

“…Recently, we found that TppBr could exhibit different crystallization features under the varied growth conditions. Bulk crystals of TppBr could grow by spontaneous nucleation and slow evaporation of its aqueous or ethanol solution . However, as the hot water solution of TppBr was dropped on a glass slide, rapidly evaporated, and cooled, TppBr may nucleate at the edge and surface of the droplet and finally self-assemble into one-dimensional fiber crystals of several millimeters in length in a few minutes.…”

“…X-ray diffraction (XRD) spectroscopy analysis showed that both TppBr solid and tubular fibers belong to the Pnma space group with a = 16.3049 (14) Å, b = 10.8309 (9) Å, c = 12.6925 (11) Å, and α = β = γ = 90° . The structure of TppBr fibers is identical with that of its bulk crystal obtained by the spontaneous nucleation and growth in water solution (Figure a) . There are two molecules of crystal water in the lattice.…”