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Showing 1 to 16 of 16 for “"Quantum Mechanical Simulations"”.
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Advanced Quantum Mechanical Simulations of Circular Dichroism Spectra
In quantum chemistry, scientists aim to solve the time-independent Schrödinger equation by employing a variety of approximation techniques whose accuracy are typically inversely proportional to their computational cost. This problem is amplified when it comes to chiral molecules, whose …
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Evaluation of the Energetic Factors in Crystalline Pharmaceuticals Using Solid-state Density Functional Theory and Low-frequency Vibrational Spectroscopy
… vibrational spectroscopies and rigorous quantum mechanical simulations are combined to provide a new technique for characterizing and investigating pharmaceutically relevant polymorphs, hydrates, and cocrystals as well as a series of model cocrystals. Low-frequency spectra in the sub-200 …
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Einfluss dynamischer Resonanzen auf die Wechselwirkung optischer Femtosekunden-Pulse mit transparenten Dielektrika
… in the laser field. For this work I perform quantum mechanical simulations of titanium dioxide and atomic hydrogen which confirm the existence of dynamic resonances by variation of the laser field's wavelength or intensity. My numerical results corroborate the measurement of one of the …
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Elucidating the Electronic Origins of Intermolecular Forces in Crystalline Solids
… of this research was therefore placed on using quantum mechanical simulations, specifically density functional theory (DFT), to calculate the electronic properties of solid-materials. The goal of these calculations was a better understanding of the precise origins of interatomic energies, down …
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UNCOVERING FUNDAMENTAL PHYSICS OF ENERGY MATERIALS WITH QUANTUM MECHANICS, MOLECULAR DYNAMICS, AND APPLIED MACHINE LEARNING
… for future device advancement. We first leverage quantum mechanical simulations and machine learning algorithms to discover new materials for CO2 conversion and for improved sensors and communication devices. Next, we expand on these methods to develop a machine learned force field for large scale …
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Ultrafast Dynamics and Nonlinear Interactions in Alkali Atoms and Diatomics
… between 2.2 and 1.1 ps depending on the state. Quantum mechanical simulations of the wavepacket motion show excellent agreement with the experimental data. Experiments have been carried out in which atomic wavepackets interact with a four-wave mixing process in Rb and K to produce spatially and …
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A Computational Approach to Efficient Electrode Material Design for Electrochemical Oxidation of PFAS
… acid (PFOA) as a model contaminant. Through quantum mechanical simulations, the initial steps of EAOP, mainly the decarboxylation and chain-shortening reactions, are systematically explored. The effects of surface termination, PFOA orientation, explicit solvation, and applied potential are …
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Fitting Interatomic Potentials to Reproduce Phase Transitions
Due to the high computational demand of quantum mechanical simulations, researchers still rely on models for atomic interactions to simulate a large number of atoms. These so called “interatomic potentials” take a variety of forms ranging from the simple Lennard-Jones potential to machine learning …
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Systematic improvement and applications of density functional theory in complex chemical systems
… theory (DFT) has become the de facto method for quantum mechanical simulations of molecules and solids because of its high performance to cost ratio. In this thesis, we discuss two aspects of DFT simulations in complex chemical systems: systematic improvement of the accuracy of density functional …
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Dissociation dynamics of diatomic molecules in intense fields
… and their electric dipole couplings, using the quantum chemistry code GAMESS. In Chapter 6, the dissociation dynamics of the noble gas dimer ions He[subscript]2[superscript]+, Ne[subscript]2[superscript]+, Ar[subscript]2[superscript]+, Kr[subscript]2[superscript]+, and …
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Coulomb Explosion and Intense-Field Photodissociation of Ion-Beam H2+ and D2+
… mechanism. These results provide a basis for quantum mechanical simulations that could lead to a better understanding of the molecular dynamics in intense fields.
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Dynamics of lattice vibrations, molecular rotations and spins studied by terahertz spectroscopy
… their magnetic field-dependence as expected from quantum mechanical simulations, which allow precise determination of the spin energy level structures. We have demonstrated 2D THz magnetic resonance spectroscopy and its application to directly reveal the nonlinear dynamics of collective spin waves …
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Molecular Dynamics and Quantum Chemistry Studies of the Protein Bacteriorhodopsin
"Molecular dynamics (MD) simulations and Quantum Chemistry (QC) calculations are employed to study the structure and function of the protein bacteriorhodopsin (bR), a 26 kD protein which residues in the purple membrane of the bacterium Halobacterium halobium. Bacteriorhodopsin undergoes a …
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Gate-all-around silicon nanowire MOSFETs : top-down fabrication and transport enhancement techniques
… were accurately measured and verified by quantum-mechanical simulations. Increased effective hole mobility with decreasing nanowire width was observed down to 12 nm for hydrogen annealed nanowires, attributed to the smooth, high-mobility non-(100) sidewalls.
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Interplay of Transition Metals and Noncovalent Interactions in C–H Activation Catalysis
… metals in C–H activation catalysis using quantum mechanical simulations. We employ density functional theory (DFT) and wavefunction theory to perform an extensive computational study of protein HB interactions and transition metal complex (TMC) active sites in non-heme iron halogenases and …
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Quantum Mechanical/Molecular Mechanical Studies of F1-ATPase and a Plant Photoreceptor
Submitted by Meng Tao (mengtao2@illinois.edu) on 2012-10-11T20:13:47Z No. of bitstreams: 1 Dittrich.pdf: 21387898 bytes, checksum: 3039bb041b2ef5c8c1f9213547feeea4 (MD5)