Is there a slow risetime for the doublet state of chromium(III) polypyridyls?

The emission spectrum of ruthenocene: calculation of the excited-state distortions and the spacings in the repetitive pattern

“…The frequencies chosen corresponded to the main peaks and to the various sidebands in each of the two progressions. These are 18889 cm'1 (the fifth quantum of the main peak in progression II), 18722 cm"1 (the sixth quantum of the main peak in progression I), 18211 cm'1 (the seventh quantum of the main peak in progression II), 18 167 cm'1 (the first sideband of the seventh quantum of the main peak in progression II), 18 089 cm"1 (the second sideband of the seventh quantum of the main peak in progression II), 18056 cm"1 (the eigth quantum of the main peak in progression I), and 17899 cm"1 (the eighth quantum of the main peak in progression II).…”

“…Because they do appear, the point group of the excited state of ruthenocene is lower than that of the structure of the ground state, Z)2/,. 16,18 The point group in the excited state must be one in which these vibrational modes are totally symmetric. The point group that satisfies this condition is Cs.…”

Photochemistry and Photophysics of Chromium(III) Complexes

“…It has often been assumed that φ D = η isc , but this is clearly valid only when η pisc and η p are negligible. In support of the rapidity of doublet population, measurement of the rise time of doublet-state transient absorption indicated that it occurred faster than the 7 ps rise time of the laser pulse and more recently, and after some controversy, ,− the value has been refined 34 to ≤1 ps; that is, the population arises with a rate constant greater than 10 12 s -1 . It has also been observed that solvent rigidity may influence the intersystem crossing yield for Cr(en) 3 3+ , while a solvent deuterium isotope effect has been reported for Cr(bpy) 3 3+ .…”

Reversible dismutation and coordination of bis(2,4,6-triisopropylphenyl) diselenide with iodine. A model study that relates to iodine intercalation between selenium chains

“…From less bulky bis(2,3,5,6-tetramethylphenyl) diselenide (Id) with iodine, iodo(2,3,5,6-tetramethylphenyl)selane (2d), the predominant species in solution, was isolated as a pure crystalline compound. 15 The barriers of transformation of these species into each other (eq 3) are lowest for the charge-transfer complex association/ dissociation equilibria (steps i and ii are fast at all NMR time scales) and still rather low for the diselenide-diiodine dismutation (immediate equilibration according to eq 3 upon dissolving 4).…”