Vibrational time recurrences in a model of acetylene C212H2

Abstract

The time-dependent intramolecular vibrational dynamics of acetylene is investigated with the vibrogram method for the effective Hamiltonian obtained by Abbouti Temsamani and Herman [J. Chem. Phys. 102, 6371 (1995)]. The quantum recurrences evidenced by the vibrogram are shown to be in correspondence with emerging periodic orbits, especially, of the bending type. In this model, we find different kinds of bifurcations and, in particular, a birth of bending local modes as well as further bifurcations causing the destabilization of bending periodic orbits. This destabilization leads to a faster damping of the corresponding recurrences and to an increase in the intramolecular vibrational relaxation. A comparison with monodeuterated acetylene is also carried out.

Nonlinear Dynamics and Chaos in Many-Particle Hamiltonian Systems

“…In the present systems of ten ions, this local mode corresponds to the rotation of two ions with respect to the eight other ions. Such local modes are known in polyatomic molecules 45) and it is remarkable to find that they are also the feature of ion crystals. At higher energy, the crystal melts and the motion becomes very chaotic.…”

Calculated Vibrational Intensities in the ÖX̃ Electronic Transition of Acetylene

“…These studies have focused particularly on the isomerization of acetylene to the vinylidene (CCH 2 ) region of thẽ X -state potential surface. The experimental data have largely been analyzed in terms of effective Hamiltonians (23)(24)(25)(26)(27)(28)(29)(30)(31)(32), but there are a number of studies of these high vibrational states by other theoretical techniques (33)(34)(35)(36)(37)(38). A comprehensive review of the ground-state vibrational levels of acetylene is given in Ref.…”

The vibration–rotation spectrum of 12C2HD: new overtone bands and global vibrational analysis

“…Literature studies (with selected sets of references hereafter) were dedicated, in particular, to the modelling of the vibration-rotation bending states [1][2][3][4][5], the metrological investigation of the nv 3 series of vibration-rotation lines (position and intensity measurements) [6][7][8][9][10][11][12], the global modelling of the manifold of vibrational states up to very highly excited ranges [13][14][15], dynamical features [16][17][18][19][20][21], bond selected chemistry [20,22], high level ab initio calculations [23], and the application of a variety of ultra sensitive high resolution instrumental techniques [24][25][26][27][28][29][30][31][32][33][34][35][36][37][38]. A detailed description of these various features, including a complete set of references about acetylene ground state up to 1998, is provided in [13].…”