Sean Parsons

Conflict of Interests The authors declare no conflict of interest. Data Availability Statement The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.

Introduction Click to copy section linkSection link copied! The 2-cyclopenten-1-one molecule (2CP, Figure 1) is a simple conjugated enone with interesting photophysical and photochemical properties. Ultraviolet excitation of 2CP in solution prepares the S1(n, π*) state, which relaxes rapidly by intersystem crossing (ISC) to the lowest triplet excited states, T1(n, π*) and T2(π, π*).