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Updated: May 9, 2026

Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds
Published on: October 18, 2018
Hybrid MP2/MP4 potential surfaces in VSCF calculations of IR spectra: applications for organic molecules
Roie Knaanie1, Jiří Šebek, Jaroslaw Kalinowski
1Institute of Chemistry and The Fritz Haber Research Center, The Hebrew University, Jerusalem 91904, Israel.
Abstract:
This study introduces an improved hybrid MP2/MP4 ab initio potential for vibrational spectroscopy calculations which is very accurate, yet without high computational demands. The method uses harmonic vibrational calculations with the MP4(SDQ) potential to construct an improved MP2 potential by coordinate scaling. This improved MP2 potential is used for the anharmonic VSCF calculation. The method was tested spectroscopically for four molecules: butane, acetone, ethylene and glycine. Very good agreement with experiment was found. For most of the systems, the more accurate harmonic treatment considerably improved the MP2 anharmonic results.
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