Unusual Quartet-Doublet Phosphorescence from the Phosphaethynyl Radical, CP

Elavenil Ganesan; Thomas Custer; Arun-Libertsen Lawzer; Jean-Claude Guillemin; Robert Kołos

doi:10.1002/anie.202210521

Unusual Quartet-Doublet Phosphorescence from the Phosphaethynyl Radical, CP

Angew Chem Int Ed Engl. 2022 Oct 24;61(43):e202210521. doi: 10.1002/anie.202210521. Epub 2022 Sep 27.

Authors

Elavenil Ganesan¹, Thomas Custer¹, Arun-Libertsen Lawzer¹, Jean-Claude Guillemin², Robert Kołos¹

Affiliations

¹ Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.
² Univ Rennes, Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR-UMR 6226, 35000, Rennes, France.

PMID: 36052447
DOI: 10.1002/anie.202210521

Abstract

We report the first detection of phosphorescence from the phosphaethynyl radical. This rare instance of quartet-doublet emission, studied here in solid argon, is presumably promoted by efficient intersystem crossing from the originally photoexcited doublet (B² Σ⁺ ) to the adjacent second quartet state, 1⁴ Δ. Vibronic progressions were traced for the a⁴ Σ⁺ -X² Σ⁺ and a⁴ Σ⁺ -A² П_i systems from their origins up to (v'=0)→(v''=5) and (v'=0)→(v''=2) bands, respectively. The measured phosphorescence lifetime is 108 ± 3 ms.

Keywords: CP Radical; Carbon Monophosphide; Quartet-Doublet Emission; Radical Phosphorescence.