Saddle point coordinates hydrogen bonds

Figure 8.10. Normal coordinate displacement amplitudes and phases (arrows) at (a) the Cs minimum and (b) the C2h saddle point of the (HF)2 potential energy surface. Intramolecular HF bonds are drawn in thick lines. The hydrogen bond is indicated as a dashed line. (From Quack and Suhm [1991].)...

Fig. 10. A classical trajectory for cis-trans isomerization of triplet butadiene on the MINDO/3 potential surface, starting at the saddle point with an initial kinetic energy of 0.45 kcal/mol in the direction of the imaginary frequency normal coordinate. BL is bond length and T is internal rotation angle. The hydrogen bonded to C2 is denoted H2. 1 a.u. of time = 2.4xl0 s see the appendix.

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