Gas‐Phase Peptide Structures Unraveled by Far‐IR Spectroscopy: Combining IR‐UV Ion‐Dip Experiments with Born–Oppenheimer Molecular Dynamics Simulations1. Issue 14 (26th February 2014)

• Record Type: Journal Article
• Authors: Jaeqx, Sander; Oomens, Jos; Cimas, Alvaro; Gaigeot, Marie‐Pierre; Rijs, Anouk M.
• Is Part Of: Angewandte Chemie international edition. Volume 53:Issue 14(2014)
• Page Start: 3663
• Page End: 3666
• Publication Date: 2014-02-26
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201311189
• Languages: English
• ISSNs: 1433-7851

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Vibrational spectroscopy provides an important probe of the three‐dimensional structures of peptides. With increasing size, these IR spectra become very complex and to extract structural information, comparison with theoretical spectra is essential. Harmonic DFT calculations have become a common workhorse for predicting vibrational frequencies of small neutral and ionized gaseous peptides.<xref ref-type="link" rid="bib1">1</xref> Although the far‐IR region (&lt;500 cm⁻¹) may contain a wealth of structural information, as recognized in condensed phase studies, <xref ref-type="link" rid="bib2">2</xref> DFT often performs poorly in predicting the far‐IR spectra of peptides. Here, Born–Oppenheimer molecular dynamics (BOMD) is applied to predict the far‐IR signatures of two <italic>γ</italic>‐turn peptides. Combining experiments and simulations, far‐IR spectra can provide structural information on gas‐phase peptides superior to that extracted from mid‐IR and amide A features.</p> </abstract>