title: Ab initio study of the two-photon circular dichroism in chiral natural amino acids.
abstract: Two-photon circular dichroism spectra calculated within an origin-invariant density functional theory approximation in the absorption region where the lowest electronic excited states appear are presented for all 19 essential amino acids in the gas phase. A comparison of intensities and characteristic features is made with the corresponding two-photon absorption and one-photon circular dichroism spectra for each species. Also, the contributions of the electric dipole, magnetic dipole, and electric quadrupole transitions to the rotational strengths are analyzed in some detail. The remarkable fingerprinting capabilities of the two-photon circular dichroism spectroscopy are highlighted.
authors.affiliation: Istituto per i Processi Chimico-Fisici del Consiglio Nazionale delle Ricerche (IPCF-CNR), Area della Ricerca, via G. Moruzzi 1, I-56124 Pisa, Italy. jansik@chem.au.dk
authors.forename: Branislav
authors.initials: B
authors.lastname: Jansík
authors.forename: Antonio
authors.initials: A
authors.lastname: Rizzo
authors.forename: Hans
authors.initials: H
authors.lastname: Agren
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D002942:Circular Dichroism; D008956:Models, Chemical; D017785:Photons; D011789:Quantum Theory; D012680:Sensitivity and Specificity
chemical_list: D000596:Amino Acids