Density functional theory reduction

The exact nature of the catalytically active Ni species in these reactions is yet to be conclusively established. Hydrodechlorination proves optimal with a NHC Ni ratio of 2 1 suggesting that 14-electron Ni(NHC)2 is involved, whereas the 1 1 NHC Ni ratio necessary for hydrodefluorination implies that it is the 12-electron mono-carbene adduct Ni(NHC) which is catalytically active [10]. Smdies by Matsubara et al. revealed that treatment of NKacac) with either one or two equivalents of IMes HCl 1 or SlMes HCl 2 in the presence of NaOHu formed the mono-NHC complex Ni(NHC)(acac)j which, upon reduction with NaH in the presence or absence of carbene, formed Ni(NHC)2 [11]. Density functional theory (DFT) calculations suggest that the strength of the Ni-NHC bond (ca. 50 kcal/mol) makes... 

Karlberg GS, Rossmeisl J, Nprskov JK. 2007b. Estimations of electric field effects on the oxygen reduction reaction based on the density functional theory. Phys Chem Chem Phys 37 5158-5161. 

Vassilev P, Koper MTM. 2007. Electrochemical reduction of oxygen on gold surfaces A density functional theory study of intermediates reaction paths. J Phys Chem C 111 2607-2613. 

Lehnert and Tuczek further studied end-on terminal coordination by density functional theory (DFT) calculations on the compounds [Mo(N2)2(dppe)2], [MoF(NNH)(dppe)2], and [MoF(NNH2)(dppe)2]+, where dppe= 1,2-bis(diphenyl-phosphino)ethane.50 They proposed a reaction scheme, shown in reaction 6.13, for asymmetric dinitrogen reduction and protonation. The end-on model favored by Lehnert in reference 50, as shown in reaction 6.13, appears to be a less thermodynamically unfavorable pathway, at least to reach the M-NNH3 intermediate. Step 1 produces a metal-attached diazenido ion (NNH-), step 2 produces a hydrazido ion (NNH2 ), and step 3 produces a hydrazidium ion (NNHj). 

Galea NM, Kadantsev ES, and Ziegler T. Studying reduction in solid oxide fuel cell activity with density functional theory-effects of hydrogen sulfide adsorption on nickel anode surface. JPhys Chem C 2007 111 14457-14468. 

Eligh performance liquid chromatography Density functional theory Oxygen reduction reaction Rotating disk electrode Rotating ring disk electrode... 

In accordance with these experimental results, Wang et al. employed density functional theory calculations to comprehensively examine the possible reduction pathways for EC molecules in super-molecular structures Li+—(EC) [n = 1—5) and found that, thermodynamically, both one- and two-electron reductive processes are possible.A complete array of the possible reduction products from EC was listed in their paper considering the various competitive pathways, and they concluded that both (CH2OCO2-Li)2 and (CH2CH20C02Li)2 are the leading species in SEI, while minority species such as lithium alkox-ide, lithium carbide, and the inorganic Li2C03 coexist. 

Several recent papers have reported Density Functional Theory (DFT) calculations on the primary oxidation and reduction products observed in irradiated single crystals of the common nucleobases thymine [53], cytosine [54], guanine [55], and adenine [56]. The theoretical calculations include estimates of spin densities and isotropic and anisotropic hyperfine couplings which can be compared with experimental results (obtained from detailed EPR/ENDOR experiments). 

Kimura Y, Alfano JC, Walhout PK, Barbara PF (1994) Ultrafast transient absorption spectroscopy of the solvated electron in water. J Phys Chem 98 3450-3458 Li X, Sevilla MD, Sanche L (2003) Density functional theory studies of electron interaction with DNA can zero eV electrons induce strand breaks J Am Chem Soc 125 13668-13699 Lind J, Shen X, Eriksen TE, Merenyi G, Eberson L (1991) One-electron reduction of N-bromosuccin-imide. Rapid expulsion of a bromine atom. J Am Chem Soc 113 4629-4633 Marasas RA, lyoda T, Miller JR (2003) Benzene radical ion in equilibrium with solvated electrons. J Phys Chem A 107 2033-2038... 

This chapter mainly focuses on the reactivity of 02 and its partially reduced forms. Over the past 5 years, oxygen isotope fractionation has been applied to a number of mechanistic problems. The experimental and computational methods developed to examine the relevant oxidation/reduction reactions are initially discussed. The use of oxygen equilibrium isotope effects as structural probes of transition metal 02 adducts will then be presented followed by a discussion of density function theory (DFT) calculations, which have been vital to their interpretation. Following this, studies of kinetic isotope effects upon defined outer-sphere and inner-sphere reactions will be described in the context of an electron transfer theory framework. The final sections will concentrate on implications for the reaction mechanisms of metalloenzymes that react with 02, 02 -, and H202 in order to illustrate the generality of the competitive isotope fractionation method. 

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