IR-spectra of Halogenidanil under High Pressure

Metallization of Iodanil by Charge Transfer

Abstract

Infrared (IR) spectra of tetraiod-p-benzoquinone (iodanil) and tetrabromid-p-benzoquinone (bromanil) have been measured to 43 GPa at room temperature. Reversible spectral change below 43 GPa and softening behavior of C-I and C=0 stretching modes observed for iodanil indicate that the enlargement of charge transfer interactions of O…I and I…I between the adjacent molecules. Bromanil shows no softening behavior. Significant peak broadening takes place above 24 GPa, indicating polymerization.