Vibrational M–O bands of acetylacetone–metal complexes

Abstract

The Raman spectra of normal and ¹⁸O-labelled trisacetylacetonatochromium(III) were measured in the 100–1 600 cm^–1 region using a laser source. Since the ca. 355 cm^–1 band is hardly affected by ¹⁸O-labelling it cannot be due to a Cr–O stretching vibration as suggested on the basis of ⁵⁰Cr–⁵³Cr shifts. The predominantly antisymmetrical Cr–O stretching (a₂ and e) vibrations are assigned to the normal complex i.r. absorption band at 592 cm^–1.