Far infrared spectrum and associated polarisation for tris(2,4-pentandionato) aluminium in dilute benzene solution

Abstract

The far infrared spectrum between 9 and 250 cm^–1 for a dilute solution of tris(2,4-pentandionato)-aluminium in benzene has been recorded at 25°C; it exhibits a significant absorption in this region. Combination of these data with previously reported dielectric loss results indicates a significant disprersion of polarisation in the region between 0 and 120 cm^–1. By applying the Kramers–Kronig relation, the polarisation associated with this region has been calculated as ∼ 34 cm³, indicating most of the so called atomic polarisation encountered for this system is associated with this low frequency absorption region. The nature and origin of this polarisation is discussed in terms of the classical model of atomic polarisation, and a second possible mechanism involving transitory induced dipoles is proposed.