title: Communication: nanosecond folding dynamics of an alpha helix: time-dependent 2D-IR cross peaks observed using polarization-sensitive dispersed pump-probe spectroscopy.
abstract: We present a simple method to measure the dynamics of cross peaks in time-resolved two-dimensional vibrational spectroscopy. By combining suitably weighted dispersed pump-probe spectra, we eliminate the diagonal contribution to the 2D-IR response, so that the dispersed pump-probe signal contains the projection of only the cross peaks onto one of the axes of the 2D-IR spectrum. We apply the method to investigate the folding dynamics of an alpha-helical peptide in a temperature-jump experiment and find characteristic folding and unfolding time constants of 260 ± 30 and 580 ± 70 ns at 298 K.
authors: Van 't Hoff Institute for Molecular Sciences, Universiteit van Amsterdam, Amsterdam, The Netherlands.
authors: Matthijs R
authors: MR
authors: Panman
authors: Van 't Hoff Institute for Molecular Sciences, Universiteit van Amsterdam, Amsterdam, The Netherlands.
authors: Chris N
authors: CN
authors: van Dijk
authors: Van 't Hoff Institute for Molecular Sciences, Universiteit van Amsterdam, Amsterdam, The Netherlands.
authors: Heleen
authors: H
authors: Meuzelaar
authors: Van 't Hoff Institute for Molecular Sciences, Universiteit van Amsterdam, Amsterdam, The Netherlands.
authors: S
authors: S
authors: Woutersen