Vibration stretch modes

Fig. 11.31 Vibrational stretching modes and their symmetries for M(COKL complexes.

Table IV. Observed Metal-Hydroxy Hydride Vibrational Stretching Mode Frequencies (cm ), Argon Matrix, and Corresponding Diatomic Metal Fluoride Frequencies. ...

In Chapter 15 the procedure for obtaining symmetry assignments for vibrational modes from the appropriate character table will be illustrated, but for now we will simply use the results (Table 11.14). The particular vibrational stretching modes involved are shown in Fig. 11.31. The important one to focus on is which corresponds to the symmetrical stretching motion of the CO group lying opposite the ligand L. It is this CO that competes most directly with L for available tt electron density and therefore is in a position to best reflect the acidity of L. 

The fundamental of a vibrational stretching mode is observed at 2250 cm , and its first overtone is at 4450 cm What would be the frequency of the second overtone ... 

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