One hundred empirical relationships appeared in vibrational spectroscopy are collected and classified in the present work, including several of them which were reported in the literature only in the graphical form. Examples of each case are shown. The vibrational frequencies were correlated mostly in a linear way, although other types of correlations also occur, and they were related to the following basic characteristics.

 

- Structural geometrical parameters (bond lengths, bond angles and torsional angles).

- Other frequencies, temperature, pressure, etc.

 

Other spectroscopic relations refers to intensity of the vibrational bands, force constants, ¹³C-NMR chemical shift, etc. The compendium of the empirical relationships listed in this work help in the predicting of parameters used in vibrational spectroscopy.