Тип публикации: статья из журнала
Год издания: 2012
Идентификатор DOI: 10.1080/00958972.2012.672733
Ключевые слова: Palladium(II), Cystine, Kinetics, DFT, TD-DFT
Аннотация: Complex formation of PdCl42- with L-cystine (H(2)CysS) has been studied in hydrochloric aqueous solutions (0.05-1 mol L-1 HCl) by UV-Vis spectroscopy combined with quantum chemical calculations. Our data suggest that L-cystine acts as a monodentate S-coordinating ligand in highly acidic solutions and no evidence of S-S bond fissionПоказать полностьюwas found to occur under the experimental conditions. Thermodynamic parameters for Pd(H(4)CysS)Cl-3(+) formation were determined: the monocomplex stability constant log K-1 = 3.3 (298 K), Delta H = -27 kJ mol(-1), and Delta S = -29 JK(-1) mol(-1) (0.5 mol L-1 HCl). The experimental reaction rate law has been obtained: W = k[H(4)CysS(2+)][PdCl42-][Cl-](-0.86) and the values for the activation parameters have been determined: E-a = 66 kJ mol(-1), Delta H-1 = 63 kJ mol(-1), and Delta S-1 = -77 JK(-1) mol(-1). The electronic absorption spectra (EAS) of the Pd(H(4)CysS)Cl-3(+) complex were computed using time-dependent density functional theory and the polarizable continuum model. The def2-TZVPP basis set (PBE0 and TPSS density functionals) provides good agreement between the experimental and theoretical EAS.
Журнал: JOURNAL OF COORDINATION CHEMISTRY
Выпуск журнала: Vol. 65, Is. 8
Номера страниц: 1339-1353
ISSN журнала: 00958972
Место издания: ABINGDON
Издатель: TAYLOR & FRANCIS LTD