2Eg→4A2gTransition of the hexa-amminochromium(III) ion in cubic environments. Intensity mechanism and Jahn-Teller effect

Abstract

The ²E_g→⁴A_2g phosphorescence of a series of carefully purified salts containing the Cr(NH₃)³⁺ ₆ ion has been measured from 300 to 4 K. All seven τ_1u and two of the τ_2u fundamentals act as vibronic origins and the first members of progressions in the ε_g modes are observed. This is evidence for a Jahn-Teller effect in the ⁴T_2g state.