²Eg→⁴A_2gTransition of the hexa-amminochromium(III) ion in cubic environments. Intensity mechanism and Jahn-Teller effect

Abstract

The 2Eg→4A2g 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 τ1u and two of the τ2u fundamentals act as vibronic origins and the first members of progressions in the εg modes are observed. This is evidence for a Jahn-Teller effect in the 4T2g state.