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Updated: Jul 6, 2026

Raman and IR Spectroelectrochemical Methods as Tools to Analyze Conjugated Organic Compounds
Published on: October 12, 2018
Two-dimensional near-infrared correlation spectroscopy study the methanol in acidic pH region
1Center for Instrumental Analysis, China Pharmaceutical University, Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, Tongjiaxiang 24, Nanjing 210009, Jiangsu Province, People's Republic of China.
Abstract:
The effect of pH on the structure of methanol was investigated by FT-NIR (Fourier transform near-infrared) spectroscopy and generalized two-dimensional (2D) correlation spectroscopy. pH perturbed 2D correlation spectra are calculated for the spectra in the 5,500-4,000, 7,500-5,500 cm(-1) regions at different pH values. We observed that the stretching of CH(3) was shifted because of the direct interaction of the CH(3) group of methanol with the OH group of water, the change of free OH is more sensitive to pH than the cyclic dimmer and CH.O.
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