We report a combined spectroscopic and structural study of polymorphism of 1,1,4,4-tetraphenyl-1,3-butadiene (TPB) blue luminescent crystals. We have identified two polymorphs, which can be grown by crystallization of the vapor. The first, α-TPB, has the monoclinic noncentrosymmetric structure (P2 1, two molecules per unit cell), whose lattice parameters have already been reported in the literature. The second, β-TPB, is a new polymorph, monoclinic centrosymmetric (P21/c, four molecules per unit cell). The previously reported triclinic structure, γ-TPB, has not been identified in samples grown by the physical vapor transport method. The effects of the different molecular configuration and packing of α- and β-TPB on Raman scattering, IR, and UV-vis optical properties are discussed.
Girlando, A., Ianelli, S., Bilotti, I., Brillante, A., Della Valle, R., Venuti, E., et al. (2010). Spectroscopic and Structural Characterization of Two Polymorphs of 1,1,4,4-Tetraphenyl-1,3-butadiene. CRYSTAL GROWTH & DESIGN, 10(6), 2752-2758 [10.1021/cg100253k].
Spectroscopic and Structural Characterization of Two Polymorphs of 1,1,4,4-Tetraphenyl-1,3-butadiene
CAMPIONE, MARCELLO;TAVAZZI, SILVIA
2010
Abstract
We report a combined spectroscopic and structural study of polymorphism of 1,1,4,4-tetraphenyl-1,3-butadiene (TPB) blue luminescent crystals. We have identified two polymorphs, which can be grown by crystallization of the vapor. The first, α-TPB, has the monoclinic noncentrosymmetric structure (P2 1, two molecules per unit cell), whose lattice parameters have already been reported in the literature. The second, β-TPB, is a new polymorph, monoclinic centrosymmetric (P21/c, four molecules per unit cell). The previously reported triclinic structure, γ-TPB, has not been identified in samples grown by the physical vapor transport method. The effects of the different molecular configuration and packing of α- and β-TPB on Raman scattering, IR, and UV-vis optical properties are discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.