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Real time density functional simulations of quantum scale conductance
(Massachusetts Institute of Technology, 2009)
We study electronic conductance through single molecules by subjecting a molecular junction to a time dependent potential and propagating the electronic state in real time using time-dependent density functional theory ...
Electronic signatures of large amplitude motions
(Massachusetts Institute of Technology, 2009)
In this thesis, I demonstrate that measurements of electronic-structure-induced splittings in the rotational spectrum of a vibrationally excited state can identify the nature and extent of the distortion of the equilibrium ...
Investigations of the inhibition mechanisms of human ribonucleotide reductase by gemcitabine-5'-diphosphate and saccharomyces cerevisiae ribonucleotide reductase by Sml1
(Massachusetts Institute of Technology, 2009)
Ribonucleotide reductases (RNRs) catalyze the conversion of nucleotides to deoxynucleotides supplying the dNTPs required for DNA replication and DNA repair. Class I RNRs require two subunits ([alpha] and [beta]) for activity. ...
Progress in nucleophilic catalysis and development of nickel-catalyzed cross-couplings of propargylic halides
(Massachusetts Institute of Technology, 2009)
Chapter 1 describes the development of two organocatalytic processes. The first is a 13-alkylation reaction of Michael acceptors, and represents a novel umpolung process catalyzed by N-heterocyclic carbenes. The second ...
Spectroscopic investigation of photo-induced proton-coupled electron transfer and Dexter energy transfer in model systems
(Massachusetts Institute of Technology, 2009)
Spectroscopic investigations of systems designed to advance the mechanistic interrogation of photo-induced proton coupled electron transfer (PCET) and proton-coupled (through-bond) energy transfer (PCEnT) are presented. ...
Dinitrogen fixation chemistry of a molybdenum trisanilide system
(Massachusetts Institute of Technology, 2009)
Dinitrogen cleavage by Mo(N[t-Bu]Ar)3 (Ar = 3,5-C6H3Me2) proceeds through the intermediate ([mu]-N2)[Mo(N[t-Bu]Ar)3]2 before forming N=Mo(N[t-Bu]Ar)3 as the product. Both the intermediate bridging N2 complex and the nitride ...
Niobium-mediated generation of P-P multiply bonded intermediates
(Massachusetts Institute of Technology, 2009)
The diphosphaazide complex (MesNPP)Nb(N[CH2 tBu]Ar)3, 1 (Mes = 2,4,6-tri-tert-butylphenyl, Ar = 3,5-dimethylphenyl), releases a P2 unit upon heating to form MesNNb(N[CH2 tBu]Ar)3, 2, in a first-order process. The chemistry ...
The generation of high field terahertz radiation and its application in terahertz nonlinear spectroscopy
(Massachusetts Institute of Technology, 2009)
In this thesis research, I implemented a terahertz generation scheme that enables high-field near-single-cycle terahertz (THz) pulse generation via optical rectification in a LiNbO3 (LN) crystal. I also developed a method ...
Non-traditional platinum compounds for improved cellular accumulation and tumor targeting
(Massachusetts Institute of Technology, 2009)
Chapter 1. Introduction to Non-Traditional Platinum Compounds for Improved Uptake, Oral Bioavailability, and Tumor Targeting The path to more potent platinum anticancer drugs with fewer side effects lies in the exploration ...
Spectroscopic signatures of doorway-mediated intersystem crossing
(Massachusetts Institute of Technology, 2009)
Intersystem crossing in acetylene, C₂H₂, is described by a doorway-mediated model, where singlet-triplet mixing between the first excited singlet~ state, S₁, and the manifold of low-lying T₁,₂ states is controlled by special ...