CHEMISTRY 110 - Dr

Why would you expect the Raman spectrum to show a strong absorbance at ~1400 cm-1 (weak or missing in IR spectrum), while the IR spectrum shows a strong absorbance at 1690 cm-1 (weak or missing in the Raman spectrum)? Raman spectroscopy is sensitive to symmetrical stretches, change in polarization, that would occur for a C-C bond at ~1400 cm-1. ................
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