This is a ATR spectrum. In which caffeine/PVA films were measured. Line a) correspond to a pure pva film and the other lines are films at increasing caffeine concentration. Notice that the OH band at around 3200cm-1 decreases at higher caffeine concentrations. However at a certain concentration (line d) such band starts to increase back to the initial intensity. What does that mean? Waht is the chemical meaning for that behavior?

This is a ATR spectrum. In which caffeine/PVA films were measured. Line a) correspond to a pure pva film and the other lines are films at increasing caffeine concentration. Notice that the OH band at around 3200cm-1 decreases at higher caffeine concentrations. However at a certain concentration (line d) such band starts to increase back to the initial intensity. What does that mean? Waht is the chemical meaning for that behavior?

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter24: Introduction To Spectrochemical Methods

Section: Chapter Questions

Problem 24.2QAP

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