Author/Authors :
Wojciechowski، نويسنده , , R and Ulanski، نويسنده , , J and Lefrant، نويسنده , , S and Faulques، نويسنده , , E and Laukhina، نويسنده , , E and Tkacheva، نويسنده , , V، نويسنده ,
Abstract :
The Raman spectra of β″-(ET)2Br0.5ICl1.5 single crystals (where ET=bis(ethylenodithio) tetrathiafulvalene) were investigated at 25 and at 80 K for the (001) crystallographic plane. The comparison with the spectra for β″-(ET)2ICl2 and β-(ET)2IBr2 indicates the presence of a mixture of (Br–I–Br)−, (Br–I–Cl)− and (Cl–I–Cl)− anions in the β″-(ET)2Br0.5ICl1.5 single crystals. The angular dependence of the Raman spectra obtained at 80 K by rotating the single crystal by π/8 for fixed polarisation of the incident laser light confirms the assignment of the observed bands to three different trihalide anions. It was found for β″-(ET)2Br0.5ICl1.5 and β″-ET2ICl2, that internal vibrations of ET molecule are the strongest and very well resolved for polarisation parallel to the [100].
