Abstract
We present a computational methodology to calculate the intensity of circular dichroism (CD) in spinforbidden
absorption and of circularly polarized phosphorescence (CPP) signals, a manifestation of the
optical activity of the triplet–singlet transitions in chiral compounds. The protocol is based on the
response function formalism and is implemented at the level of time-dependent density functional
theory. It has been employed to calculate the spin-forbidden circular dichroism and circularly polarized
phosphorescence signals of valence n → p* and n ← p* transitions, respectively, in several chiral
enones and diketones. Basis set effects in the length and velocity gauge formulations have been
explored, and the accuracy achieved when employing approximate (mean-field and effective nuclear
charge) spin–orbit operators has been investigated. CPP is shown to be a sensitive probe of the triplet
excited state structure. In many cases the sign of the spin-forbidden CD and CPP signals are opposite.
For the b,g-enones under investigation, where there are two minima on the lowest triplet excited state
potential energy surface, each minimum exhibits a CPP signal of a different sign
Original language | English |
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Journal | Physical Chemistry Chemical Physics |
Volume | 17 |
Issue number | 29 |
Pages (from-to) | 19079-19086 |
Number of pages | 8 |
ISSN | 1463-9076 |
DOIs | |
Publication status | Published - 2015 |
Externally published | Yes |