Triplet, energy levels, determination mechanisms

Fig. 29. Energy level diagram for Pt(2-thpy)2 dissolved in n-octane. The electronic origin line I (0-0 transition) is not observed at zero magnetic field. The corresponding triplet substate I is radiatively deactivated via vibronic (HT = Herzberg-Teller) mechanisms. (Compare Fig. 13.) The emission lifetime given refers to T=1.3 K. The emissions from the triplet substates II and III are intense at the electronic origins and show vibrational Franck-Condon (FC) satellites. (Compare Fig. 14.) The lifetime of the Sj state of 50 fs is determined from the homogeneous linewidth of the Sq Si electronic transition at T = 1.3 K. (Compare Fig. 28)...

Fig. 25 Potential energy surfaces for the most feasible two-state reaction pathways for ethylene dimerization catalyzed by Cr(II)OH (If), via either a Cr-carbene mechanism or a metallacycle mechanism determined at the M06 level of theory. Also shown are the crossing points optimized at CASSCF level. The triplet metallacycle reaction pathway is depicted in blue, and the triplet Cr-carbene reaction pathway is shown in dark red. The quintet parts are in black. Energies are in kcal moP and relative to il. Bond lengths are in angstroms. Angles are in degrees...

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