Search for dissertations about: "pt 111"

Showing result 1 - 5 of 30 swedish dissertations containing the words pt 111.

2. 1. Infrared spectroscopy of O2 and N2 adsorption on the clean and hydrogen covered Pt(111) surface

   Author : Kristian Gustafsson; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Infrared Spectroscopy; Adsorption; Hydrogen; Nitrogen; Pt 111 ; Oxygen;

   Abstract : This thesis is devoted to the investigation of O2and N2 adsorption on the clean and the hydrogen covered Pt(111) surface. Using infrared reflection absorption spectroscopy (IRAS) both physisorbed and chemisorbed molecular adsorptionstates have been identified and characterized via theircharacteristic internal vibration spectra. READ MORE

4. 2. Low-Energy Modes of Molecules and Atoms Chemisorbed on a Metal Surface. CO and O on Pt(111) Studied by Infrared Spectroscopy

   Author : Ulrika Engström; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; dipole-allowed modes; low-energy modes; carbon monoxide; Infrared spectroscopy; dipole-forbidden modes; Pt 111 ; anti-absorption; Fermi resonance; atomic oxygen;

   Abstract : This thesis is devoted to the investigation of low-energy metal-adsorbate vibrational modes of CO molecules and O atoms chemisorbed on a Pt(111) surface using infrared spectroscopy (IRS). The infrared selection rule states that only vibrational modes having a non-vanishing component of its dynamical dipole moment perpendicular to the surface can be directly excited using IRS, known as dipole-allowed modes. READ MORE

5. 3. Using Light to Probe Surface Electrochemical Processes

   Author : Weronica Linpe; NanoLund: Centre for Nanoscience; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Electrochemistry; X-ray methods; In situ; synchrotron radiation; Ex situ; Single crystal; polycrystalline; aluminium oxide; Au; Pd; Pt; Sn; Super duplex stainless steel.; Fysicumarkivet A:2021:Linpé;

   Abstract : This thesis shows how various light-based in situ techniques can be used to follow different surface electrochemical processes such as electrochemical deposition into Nanoporous Anodic Aluminium Oxide (NP-AAO) templates and the surface structure of electrodes. Techniques based on both x-rays and visible light were used to follow surface structures and compositions, in situ. READ MORE

6. 4. Global bifurcations and chaotic dynamics in physical applications

   Author : Martín G. Zimmermann; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Quantum chemistry; Global bifurcations; Šil´nikov phenomenon; degenerate homoclinic orbit; onset of spatiotemporal chaos; heteroclinic cycles; orientation- and inclination-flip bifurcations; Kvantkemi; Quantum chemistry; Kvantkemi; Quantum Chemistry; kvantkemi;

   Abstract : The aim of this work has been to analyse global bifurcations arising in a laser with injectedsignal and in a catalytic reaction on a surface of Pt, from the point of view of dynamicalsystems theory.The 3-dimensional ordinary differential equation which models the laser was found to contain a homoclinic orbit to a saddle-focus equilibrium, what corresponds to the Šil´nikov phenomenon. READ MORE

7. 5. Adsorption and bonding on platinum : influence of the surface structure and chemical composition

   Author : Emmanuelle Janin; KTH; []
   Keywords : Platinum; tin; low index single crystal surfaces; adsorption;

   Abstract : This thesis deals with the influence of the structure andchemical composition of platinum surfaces on the adsorption ofsome molecules. Three main lines can be distinguished : 1) thecharacterisation of clean/modified surfaces, 2) the adsorptionof some simple atoms and molecules on these surfaces andfinally 3) the adsorption of 2-butenal, a bi-functionalmolecule containing a C=C group conjugated with a C=O group. READ MORE