title: Structures and Energetics of Protonated Clusters of Methylamine with Phenylalanine Analogs, Characterized by Infrared Multiple Photon Dissociation Spectroscopy and Electronic Structure Calculations.
abstract: Gas-phase clusters of protonated methylamine and phenylalanine (Phe) derivatives have been studied using infrared multiple photon dissociation (IRMPD) spectroscopy in combination with electronic structure calculations at the MP2/aug-cc-pVTZ//B3LYP/6-311+G(d,p) level of theory. Experiments were performed on several Phe derivatives including 4-chloro-l-phenylalanine (4Chloro-Phe), 4-nitro-l-phenylalanine (4Nitro-Phe), 3-cyano-l-phenylalanine (3Cyano-Phe), and 3-trifluoromethyl-l-phenylalanine (3CF3-Phe). Through comparisons between experimental IRMPD spectra and stimulated spectra obtained by electronic structure calculations, charge-solvated structures were found to be prevalent in both 4Chloro-Phe and 4Nitro-Phe, whereas 3Cyano-Phe favored zwitterionic structures and 3-CF3-Phe likely have both zwitterionic and charge-solvated structures present.
authors.affiliation: Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Kleisath
authors.affiliation: Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
authors.forename: Rick A
authors.initials: RA
authors.lastname: Marta
authors.affiliation: Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Martens
authors.affiliation: Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
authors.forename: Jon
authors.initials: J
authors.lastname: Martens
authors.affiliation: Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
authors.forename: Terry
authors.initials: T
authors.lastname: McMahon
mesh_terms: D003198:Computer Simulation; D005740:Gases / Q000737:chemistry*; D008744:Methylamines / Q000737:chemistry*; D008956:Models, Chemical; D015394:Molecular Structure; D010649:Phenylalanine / Q000031:analogs & derivatives*; D011522:Protons; D013055:Spectrophotometry, Infrared
chemical_list: D005740:Gases; D008744:Methylamines; D011522:Protons; D010649:Phenylalanine; C027451:methylamine