Sökning: "initio molecular-dynamics"

Visar resultat 1 - 5 av 76 avhandlingar innehållade orden initio molecular-dynamics.

1. 1. Algorithms for Molecular Dynamics Simulations

   Författare :Fredrik Hedman; Aatto Laaksonen; Tom Darden; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; molecular dynamics; MD; first principles molecular dynamics; quantum mechanics; liquid water; parallel algorithm; data parallel; MPI; Coulombic interaction; Ewald summation; nonuniform fast Fourier transform; FFT; FFTW; NFFT; ENUF; Physical chemistry; Fysikalisk kemi;

   Sammanfattning : Methods for performing large-scale parallel Molecular Dynamics(MD) simulations are investigated. A perspective on the field of parallel MD simulations is given. Hardware and software aspects are characterized and the interplay between the two is briefly discussed. LÄS MER

3. 2. Studies of Material Properties using Ab Initio and Classical Molecular Dynamics

   Författare :Love Koči; Börje Johansson; Rajeev Ahuja; Dario Alfè; Uppsala universitet; []
   Nyckelord :Atomic and molecular physics; molecular dynamics; phase transitions; melting; elasticity; equation of state; metals; rare gases; Atom- och molekylfysik;

   Sammanfattning : In this thesis, material properties have been examined under extreme conditions in computer-based calculations.The research on iron (Fe), nickel (Ni), and ferropericlase (Mg1-xFexO) are not only important for our understanding of the Earth, but also for an improved knowledge of these materials per se. LÄS MER

4. 3. Combined Molecular Dynamics and Embedded-Cluster Calculations in Metal Oxide Surface Chemistry

   Författare :Björn Herschend; Kersti Hermansson; Micael Baudin; Joachim Sauer; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Inorganic chemistry; embedded-cluster; ab initio; molecular dynamics; metal oxide; ceria; magnesium oxide; adsorption; surface defect; Oorganisk kemi; Inorganic chemistry; Oorganisk kemi;

   Sammanfattning : The development and improvement of the functionality of metal oxides in heterogeneous catalysis and other surface chemical processes can greatly benefit from an atomic-level understanding of the surface chemistry. Atomistic calculations such as quantum mechanical (QM) calculations and molecular dynamics (MD) simulations can provide highly detailed information about the atomic and electronic structure, and constitute valuable complements to experimental surface science techniques. LÄS MER

5. 4. The water molecule in gaseous, liquid and solid surroundings : an ab initio molecular dynamics study

   Författare :Lars Ojamäe; Uppsala universitet; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP;

   Sammanfattning : .... LÄS MER

7. 5. Numerical Methods for Molecular Dynamics with Nearly Crossing Potential Surfaces

   Författare :Ashraful Kadir; Anders Szepessy; Emanuel Rubensson; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Numerical Methods; Molecular Dynamics; Nearly Crossing Potential Surfaces; Error Estimation; Adaptive Algorithm; Tillämpad matematik och beräkningsmatematik; Applied and Computational Mathematics;

   Sammanfattning : This thesis consists of four papers that concern error estimates for the Born-Oppenheimer molecular dynamics, and adaptive algorithms for the Car-Parrinello and Ehrenfest molecular dynamics.In Paper I, we study error estimates for the Born-Oppenheimer molecular dynamics with nearly crossing potential surfaces. LÄS MER