Vibrational spectra of vitreous SiO2 and vitreous GeO2 from first principles
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We describe the use of stimulated Raman pumping in a molecular beam to perform quantum state resolved gas-surface reactivity measurements for molecules prepared in totally symmetric vibrational states. Vibrational states of homonuclear diatomics as well as ...
We analyze the principal vibrational spectra of vitreous GeO2 and derive therefrom structural properties referring to length scales beyond the basic tetrahedral unit. We generate a model structure that yields a neutron structure factor in accord with exper ...
Metal cation-acetylene complexes (M = V, Fe, Co, Ni) are produced in mol. beams and studied with IR photodissocn. spectroscopy in the C-H stretching region. Each complex has two vibrational bands corresponding to the sym. and asym. stretches of acetylene t ...
We describe a scheme for calculating the infrared and Raman spectra of large model structures from first principles. Our scheme is based on the application of a finite electric field in density functional calculations with periodic boundary conditions. Cou ...
We determine the fraction f of B atoms belonging to boroxol rings in vitreous boron oxide through a first-principles analysis. After generating a model structure of vitreous B2O3 by first-principles molecular dynamics, we address a large set of properties, ...
The state-resolved reactivity of CH4 in its totally symmetric C-H stretch vibration (nu(1)) has been measured on a Ni(100) surface. Methane molecules were accelerated to kinetic energies of 49 and 63.5 kJ/mol in a molecular beam and vibrationally excited t ...
Spectra of jet-cooled methanol in the overtone and combination region from 5000 to, 14000 cm(-1) have been obtained by means of infrared laser-assisted photofragment spectroscopy. Many of the observed features are assigned to combination bands of the type ...
In this work, the state-resolved reactivity of methane excited to different C-H stretch vibrations have been measured on a Ni(100) surface. Two kinds of experiments have been performed. In the first series of experiments, we have measured the reactivity of ...
The HH and HV Raman spectra of vitreous silica are calculated from first principles for a model structure consisting of a disordered network of corner-sharing tetrahedra, for which the vibrational properties were obtained previously. We analyse the contrib ...
This thesis is devoted to the study of Raman scattering from first-principles. We develop two different methods to calculate Raman spectra of large model structures. The first method concerns the extension of the perturbative variational approach for the c ...