Assignment of the lattice modes in TCNQ0 single crystals

Abstract

A complete assignment of the six librational modes of the TCNQ0 crystal has been made employing both polarized Raman spectroscopic measurements and lattice dynamical calculations. Agreement between theory and experiment is good and modes at 40.5, 74.5, and 96 cm-1 are assigned as Ag active and those at 63, 75.5, and 104 cm-1 are Bg active. The lattice modes are found to be clearly separated from the molecular modes. The study emphasizes the importance of crystal optics and quality in the measurement of the polarized Raman spectra of biaxial crystals. © 1986 American Institute of Physics.