Mode damping

Figure 14. Narrowing of the lineshapes by the slow mode damping (T = 300 K).

Figure 17. Lineshapes involving both direct and slow mode damping (dots) as compared to those involving only direct damping (lines). In each column, the ad hoc dampings ( y0 for the full lines, ya and yXl for the dotted lines) are decreased (from top to bottom) from 0.8 to 0.6 and 0.4. The middle column corresponds to the H species at 300 K, the right one corresponds to the D ones at the same temperature, and the left one corresponds to the H ones but at O 100 K. a0 = 1.5, (0o = 3000cm-1, lo, = 150cm 1.

These conclusions must be considered keeping in mind that the general theoretical spectral density used for the computations, in the absence of the fast mode damping, reduces [8] to the Boulil et al. spectral density and, in the absence of the slow mode damping, reduces to that obtained by Rosch and Ratner one must also rember that these two last spectral densities, in the absence of both dampings [8], reduce to the Franck-Condon progression involving Dirac delta peaks that are the result of the fundamental work of Marechal and Witkowski. Besides, the adiabatic approximation at the basis of the Marechal... 

The good scaling between collective-mode damping induced by thermally activated quasiparticles (as already known for CDW systems). 

Pytte E (1970) Soft-mode damping and ultrasonic attenuation at a stmctural phase transition. Phys Rev B 1 924-930... 

First natural frequency [Hz] First mode damping [%] Second natural frequency [Hz] Second mode damping [%] First natural frequency [Hz] First mode damping [%] Second natural frequency [Hz] Second mode damping [%]... 

Mixed In-Height Concrete-Steel Buildings Under Seismic Actions Modeling and Analysis, Fig. 17 First mode damping ratio... 

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