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RESEARCH PRODUCT

STUDY OF THE INTERNAL DYNAMICS OF NON PLANAR PYRAMIDAL MOLECULES IN VIBRATIONALY VERY EXCITED STATES.

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description

From the U (p+1) formalism, we built a Hamiltonian adapted to the stretching modes of nonplanar XY3 molecules having the C3v group of geometrical invariance. This Hamiltonian is then coupled with two possible Hamiltonians describing the bending modes of these molecular system: a) based on the U (p+1) approach, a bending Hamiltonian is developed and the interaction between the bending and the stretching modes is taking into account through adapted 2:1 resonance coupling operator defined as a Us(4) x Ub(4) enveloping algebra operator ; b) based on the standard normal modes formalism, a bending modes Hamiltonian is expanded and the 2:1 interaction is taken into account as a tensorial product of a Us(4) operator with a standard normal one for the bending. These formalisms are then apply to stibine, phosphine and arsine molecules and compare with previous studies. The quantum number of polyad allows perform a computer modelling of the problem particulary for the process of Hamiltonian matrix diagonalization. The numerical codes and computering processes are explained in this thesis work. The entire thesis is in French with an equivalent translation in Russian.