Publications [#233705] of Richard A. Palmer

Journal Articles

  1. Palmer, RA; Plunkett, SE; Dyer, RB; Schoonover, JS; Meyer, TJ; Chao, JL, "The application of time-resolved step-scan FT-IR to the photodynamics of transition metal complexes and heme proteins", edited by Bertie, JE; Wieser, H , Proceedings of SPIE - The International Society for Optical EngineeringJanuary,, 1994, 2089, 488-489, SPIE-INT SOC OPTICAL ENGINEERING [Gateway.cgi], [doi].
    (last updated on 2024/11/19)

    Abstract:
    Time-resolved step-scan FT-IR spectroscopy is used to monitor two distinct photo-induced processes. In the first, the third harmonic of a pulsed Nd: Y AG laser (355 nm) is used to initiate a metal-to-ligand charge transfer process (MLCT) in a number of Ru(II) and/or Re(I) polypyridyl complexes. Changes in the position and shape of the vibrational signatures of rc-backbonding ligands such as CO and/or CN provide information about the changes in oxidation state of the metal resulting from electronic excitation. Changes in the other ligands vibrational bands indicate which is the electron acceptor (radical anion). In the second example demonstrated here, the second harmonic of the Nd:YAG laser (532 nm) pumps into the β-Visible band of carbonmonoxymyoglobin (MbCO). This dissociates the Fe-CO bond of the heme prosthetic group, and the recombination process is observed as indicated by changes in the amide bands of the polypeptide chain. In both cases, these are some of the very few examples of fast (sub-μs) TR FT-IR in the absorbance mode.