S1 Supplement to: Vibrational Signatures of Conformer-Specific Intramolecular Interactions in Protonated Tryptophan Aleksandr Y. Pereverzev, a Xiaolu Cheng, b Natalia S. Nagornova, a Diana L. Reese, b Ryan P. Steele, b, ** and Oleg V. Boyarkin a, * a Laboratoire de Chimie Physique Moléculaire, Ecole Polytechnique Federale de Lausanne, EPFL SB ISIC LCPM, Station 6, CH-1015 Lausanne, Switzerland b Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, UT 84112 Henry Eyring Center for Theoretical Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, UT 84112 Corresponding Authors *Author to whom correspondence should be addressed (experiments). Electronic mail address: oleg.boiarkin@epfl.ch **Author to whom correspondence should be addressed (computations). Electronic mail address: ryan.steele@utah.edu