Sökning: "Car-Parrinello molecular dynamics"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden Car-Parrinello molecular dynamics.

1. 1. Classical and Car-Parrinello Molecular Dynamics Simulations of Polyvalent Metal Ions in Water

   Författare :Sami Amira; Kersti Hermansson; Imre Bako; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Inorganic chemistry; Car-Parrinello molecular dynamics simulations; ab initio calculations; ion; copper; aluminium; metal ion; water; aqueous solution; solvation; Oorganisk kemi; Inorganic chemistry; Oorganisk kemi;

   Sammanfattning : The aqueous solvation of metal ions is one of the long-standing and complex problems in chemistry, with implications for and applications in a broad range of biochemical and electrochemical systems, where water is the all-pervasive medium.This thesis describes computer simulations of Al3+(aq), Fe2+(aq), Fe3+(aq) and Cu2+(aq). LÄS MER

3. 2. Quantum Mechanical Calculations of Thermoelectrical Polymers and Organic Molecules

   Författare :Amina Mirsakiyeva; Anna Delin; Clas Persson; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Quantum molecular dynamics; Car-Parrinello molecular dynamics; PEDOT; poly 3; 4-ethylenedioxythiophene ; Fysik; Physics;

   Sammanfattning : The subject of the present licentiate thesis is density functional theorybased electronic structure calculations of organic thermoelectric materials and novel organic molecules. We used the Car-Parrinello molecular dynamics method in order to investigate the electronic structure of “green energy” and “greenchemistry” compounds. LÄS MER

4. 3. Ultrafast Photo-induced Reaction Dynamics of Small Molecules

   Författare :Malin Kadi; Jan Davidsson; Eva Åkesson; Sören Keiding; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; pump-probe spectroscopy; reaction dynamics; photodissociation; aryl halides; spin-orbit coupling; ab initio calculations; molecular dynamics; vibrational wavepackets; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi;

   Sammanfattning : The main focus of this thesis is the investigation of the dissociation dynamics of aryl halides using femtosecond pump-probe spectroscopy. In the monohalogenated aryl halides, iodo-, bromo- and chlorobenzene, the rate of dissociation following excitation at 266 nm in the gas phase increased with increasing mass of the halogen atom. LÄS MER

5. 4. 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

7. 5. Electronic and optical properties of conducting polymers from quantum mechanical computations

   Författare :Amina Mirsakiyeva; Anna Delin; Igor Zozoulenko; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; density functional theory; DFT; Car-Parrinello molecular dynamics; CPMD; tigh-binding; poly 3; 4-ethylenedioxythiophene ; PEDOT; selenium; PEDOS; tellurium; PEDOTe; poly p-phenylene ; poly para-phenylene ; poly 1; 4-phenylene ; naphthobischalcogenadiazoles; Fysik; Physics;

   Sammanfattning :     Conductive polymers are also known as "organic metals" due to their semiconducting properties. They are found in a wide range of applications in the field of organic electronics. However, the growing number of experimental works is not widely supported with theoretical calculations. LÄS MER