Electronically excited molecules potential energy diagram

Figure 7. Potential energy diagram of CH2O. After excitation to specific rovibrational levels of Si, internal conversion leads to highly excited molecules in the ground electronic state So, whereas intersystem crossing populates the lowest triplet state Ti.

Figure 28-1 Schematic potential-energy diagram for ground and excited electronic states of a diatomic molecule A—B. The horizontal lines represent vibrational energy levels (Section 9-7). Absorption of a photon induces a transition from ground-state singlet to excited singlet...

Fig. 9. Potential energy diagram for breaking chemical bonds in an energetic molecule. The specific coordinate R shown here is identified as the reaction coordinate. In ascending energy these levels are the electronic ground state, a bound excited state and a dissociative excited state. Thermal cleavage of a bond in the electronic ground state requires a minimum energy Dq. In bound electronic states the bond dissociation energy Do is usually smaller than Do, so thermochemistry often has a lower barrier electronic excited states. Chemical bonds can also be broken by electronic excitation to predissociative or dissociative electronic states.

O Use potential energy diagrams and selection rules to predict the processes resulting from electronic excitation of a molecule. 

An excimer is a molecule, such as ArF or XeCl, with a potential energy diagram of the sort diagrammed in the following figure. The two lowest-energy electronic states are shown. Explain briefly what happens to the molecule after it is formed in the AD excited state. 

The determining feature by which laser action can be efficiently obtained from this type of active medium is the fact that the atoms that form the dimmer are only bound in the excited state. Figure 2.9 shows a schematic diagram of the laser energy levels in a molecule of excimer. The laser transition is produced between two molecular electronic levels in which the potential energy curve for the fundamental state is repulsive. This ensures the population inversion. 

Fig. 7. Schematic diagram showing the difference in the redox properties of the ground and excited molecule according to Eqs. (12) and (13) c is the one-electron potential corresponding to the zero-zero spectroscopic energy of the excited state...

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