FIR Absorption in Monoclinic ZnAs2

FIR absorption in powdered ZnAs2 crystals is studied. The features within the frequency area 194 to 270 cm−1 are attributed to As helix modes. Low-frequency features are attributed to modes involving important contributions of Zn atoms. There are some indications that inter-As helix correlation splitting exists. L'absorption dans l'infrarouge lointain des cristaux en poudre du ZnAs2, est etudiee. Les bandes aux frequences de l'interval 194 a 270 cm−1 sont attribuees aux modes des As helices. Celles aux basses frequences sont attribuees aux modes avec une contribution importante d'atomes du Zn. Il y a des indications qu'un fondage de correlation due aux interactions parmi des As helices peut exister.