Y is being investigated not only for a better understanding of the orientation of molecules in crystals, solution and the liquid phase, but also for its role in biological, chemical and catalytic processes. The time-scale allows each different conformer to be seen separately and the spectral characteristics of the XH vibrations accurately reflect the dynamics of the interacting or sensing proton. Y interaction in crystallisation and in the formation of associates is still not fully recognised and characterisation of functional variability of these bonds is needed for a better understanding of interaction mechanisms. Both qualitative and quantitative analysis of infrared and Raman spectra may profit by the application of multivariate methods. Temperature, solvent, concentration and polarisation induced spectral changes are being investigated as a possible source of structural information.
Multivariate techniques are imperative for a detailed analysis of the data.
Also, these techniques can be useful in quantifying relations between chemical or physical properties of complex samples and vibrational spectra.